Patent Application
20210162325
The invention relates to a separator device for separating fibrous material from wastewater, having a housing comprising at least one inlet for wastewater, at least one first outlet for filtrate, and at least one second outlet for the fibrous material, and having at least one hollow strainer element disposed in the housing, the inlet opening into the interior of the strainer element and the first outlet being disposed in an intermediate space between the housing and the strainer element. The invention further relates to a method for separating fibrous material from wastewater, preferably using a separator device of the type indicted above.
Separator devices of the type indicated above are used for filtering wastewater, such as wastewater from sewage treatment plants, but also liquid manure. One problem that arises thereby is that the strainer element quickly becomes blocked by the fibrous material and must therefore be backflushed. The fibrous material should then be removed during or after the filtration process. But the more the fibrous material can be dehydrated, the greater the accumulation of nutrients, and the filter cake or sludge should therefore be extensively dehydrated.
A separator device is known from DE 27 577 46, for example, wherein a cylindrical strainer element is oriented substantially horizontally and liquid can pass through the strainer element radially from the exterior to the interior. In order to achieve backflushing, wings are provided in the interior of the strainer element and tightly guided along the inner surface thereof in order to bring about a liquid impulse through the wall of the strainer element, so that fibrous material is separated from the same.
DE 690 03 110 T2 discloses a vertically oriented separator having two strainer elements placed concentrically one inside the other. A foil is disposed between said inner and outer strainer elements and rotates and travels along between said elements in order to bring about an impulse in turn and thus to achieve backflushing. The foils are substantially implemented as wings.
A separator modified with respect to the above is disclosed by WO 2002 26348 A1. The separator disclosed therein comprises a stationary and substantially cylindrical strainer element. The strainer element is placed in a housing. An opening opens into the strainer element from above. An outlet for the fibrous material is disposed at the bottom end of the strainer element and an outlet for the filtrate is disposed radially to the strainer element. A drive is provided for moving a barrel-shaped body within the strainer element in order to press the fibrous material against a radially internal surface of the strainer element. Backflushing, however, takes place here at best indirectly, and the strainer element cannot be prevented from becoming blocked over the long term.
Two separators are known from WO 2011 002317 A1 and WO 2016 009357 A1 and are oriented horizontally. A screw or displacement element is disposed in the interior of the strainer element and can transport liquid horizontally while pressing fibrous material against the radially internal surface of the strainer element in order to reduce the water content. Thus for said devices, the fibers are separated out of the liquid by means of a press screw in a first step in order to then filter out smaller particles in a second step.
In addition to such separators working with substantially cylindrical strainer elements, there also exist separators working with substantially flat vibrating screens. One such solution is disclosed in DE 10 2016 008 266 A1. In addition to the vibrating screen disposed at an angle for transporting the filter cake to an outlet due to the vibrating motion, said solution comprises interchangeable screen fixtures for disposing on the vibrating screen. While the transporting of the filter cake to the outlet functions well, the design is complex and many components are required.
Overall, the design of the known separators is complex, and effective backflushing is generally not possible. In addition, two-stage processes using a pressing screw and a downstream filter are complex and not efficient.
The object of the present invention is to disclose a separator device of the type indicated above that is improved with respect to the problems of the prior art. The separator device is to be particularly simple in design, allow effective backflushing, and be able to operate continuously.
The object is achieved by the invention as a separator device of the type indicated above in that the at least one strainer element is movably arranged in the housing and is coupled to a drive for displacing the strainer element.
Unlike the prior art, no stationary strainer element is used in the present invention, but rather a movable element. The strainer element is moved by means of the drive, whereby liquid inside and outside the strainer element is also set in motion, so that backflushing of the strainer element is possible, depending on the direction of motion. The housing preferably forms a tank for the strainer element and said element can be disposed in said tank.
A further separator housing can also be provided for enclosing the entire device.
The various connections are provided for feeding in and discharging the corresponding liquids and/or solids. The inlet for wastewater opens into the interior of the strainer element in order to introduce the wastewater carrying fibrous material. The filtrate is then fed through a first outlet disposed in the intermediate space between the strainer element and the housing forming a container or a tank. A further outlet is provided for the fibrous material. Said material will typically not be completely dry, but rather take the form of a sludge able to be removed from the interior of the strainer element, for example by suctioning.
The strainer element preferably comprises a central axis. The strainer element is particularly preferably moved at least along a segment, preferably entirely, perpendicular to the central axis during operation. The strainer element is preferably substantially barrel-shaped or tube-shaped and preferably cylindrical or conical. Other shapes are also conceivable. The strainer element preferably comprises a strainer element wall enclosing the central axis in the radial direction. Said strainer element wall, preferably a cylindrical wall, forms the strainer area, while one or both end faces can be closed. The strainer element can also, however, be elliptical, rectangular, or polygonal in cross section, or can have any other arbitrary shape. The central axis is preferably an axis of symmetry, and the strainer element is preferably rotationally symmetrical. The central axis preferably extends substantially parallel to the strainer area.
Moving perpendicular to the central axis sets the liquid inside and outside the strainer element in motion and generates a flow through the strainer element wall, said flow also being at least partially perpendicular to the central axis. The liquid carrying fibrous material is thereby pressed against the strainer element wall in the interior of the strainer element, so that said material is pressed. Filtrate is also pressed against the strainer element wall from the outside, so that backflushing of the strainer element occurs.
The strainer element is preferably rotated about an axis of rotation at least along a segment during operation. Rotation is a particularly simple motion, and ensures that backflushing is possible at every segment of the strainer element. The strainer element is thereby preferably not rotated about the central axis thereof, but rather about the axis of rotation disposed parallel to the central axis at an eccentric distance. The axis of rotation can be a central axis of the housing, for example, or an axis of rotation of an output shaft of the drive. The eccentric distance is preferably in a range from >0 to 15 mm, preferably >0 to 10 mm, >0 to 5 mm, >0 to 3 mm, >0 to 1 mm. The value >0 is 0.1 mm, 0.2 mm, or 0.5 mm in embodiments. Said value can, however, be higher.
In a preferred embodiment, the strainer element is substantially rotationally fixed about the central axis. Rotation of the strainer element about the central axis is thus substantially avoided. Rotation about axes deviating from the central axis is preferably possible. For example, the strainer element is rotationally fixed about the central axis thereof and can be rotated or moved on a circular path about an axis of rotation. The axis of rotation is preferably parallel to the central axis or is at an angle to the same. It should be understood that a substantially rotationally fixed strainer element can perform slight rotations about the central axis. wherein a maximum angle of rotation about the central axis has a value less than or equal to 90°, preferably less than or equal to 45°, particularly preferably less than or equal to 20°, further preferably less than or equal to 10°.
The rotary motion about the axis of rotation can cause wastewater received in the strainer element to rotate, and said rotation is at least partially transferred to the strainer element. It is, therefore, preferable that the separator device comprises a fixing device mounted on the strainer element implemented for substantially fixing the strainer element relative to the central axis. The fixing device preferably allows a translatory motion of the strainer element on a path, particularly a circular path. By means of the rotational fixing, it is preferably achieved that the wastewater is uniformly separated by means of the strainer element wall.
The drive preferably comprises an eccentric, wherein the strainer element is rotatably supported on the eccentric. An axis of rotation of the eccentric is implemented offset from the central axis of the strainer element. The eccentric is preferably connected to a drive shaft of the drive. The strainer element is then preferably supported on the eccentric eccentrically to a drive axis of the drive shaft. The drive shaft is preferably driven directly by means of the motor. The drive shaft can further preferably also be driven by means of a belt drive or a chain drive. The rotatable support allows rotation of the strainer element relative to the eccentric. The strainer element can preferably be moved on a circular path by means of the eccentric and the orientation thereof about the central axis is substantially retained. The strainer element retains the orientation thereof about the central axis if a reference segment of the strainer element wall during the entire rotary motion is aligned to a corresponding reference segment of the housing. It can also be provided that the strainer element is moved on a circular path and rotated about the central axis in the same or opposite rotary direction. The orientation of the strainer element thereby changes preferably periodically. The strainer element is preferably supported on the eccentric by means of at least one rolling bearing. It can also be provided that the strainer element is supported by at least one plain bearing. The strainer element preferably comprises a strainer shaft supported on the eccentric. The strainer element can thus preferably also be supported on an eccentric lug.
The central axes are particularly preferably oriented substantially vertically in operation. It is thereby possible to achieve filtering and backflushing without a pressing screw or the like being necessary. The liquid can penetrate through the strainer element wall under the force of gravitation and additional elements can be eliminated.
In a preferred refinement, the central axis of the strainer element is angled relative to the axis of rotation. The central axis or a projection of the central axis and the axis of rotation preferably enclose an angle of inclination having a value in a range from greater than 0° to 20°, preferably greater than 0° to 15°, particularly preferably 5° to 15°.
The angle of inclination is the smaller angle formed between the axis of rotation and the central axis. The axis of rotation is preferably vertically oriented and the strainer element is inclined relative to the vertical, so that wastewater impinges non-uniformly on the wall of the strainer element due to gravitational forces. Non-uniform impinging of wastewater can thereby improve backflushing of the strainer element wall and/or prevent clogging of the strainer element wall. It can also be preferable that the central axis of the strainer element is oriented vertically and the axis of rotation is inclined relative to the vertical.
The strainer element preferably performs a tumbling motion during operation. A tumbling motion is a rotation of the strainer element about the axis of rotation spaced apart from the central axis at least along a segment, wherein no rotation is performed about the central axis. The central axis preferably intersects the axis of rotation at one axis intersection during the tumbling motion. A location of the intersection point between the axis of rotation and the central axis is particularly preferably constant during the tumbling motion. The axis intersection is preferably disposed at a first end face of the strainer element disposed proximally to the drive, or at a second end face of the strainer element opposite the first end face. Wastewater to be separated is advantageously set in rotation and/or swirled by the tumbling motion, so that a separation effect is amplified and/or clogging of the strainer element with fibrous material is prevented. The central axis of the strainer element and the axis of rotation are further preferably disposed skewed to one another. The angle of inclination is then defined between the axis of rotation and a projection of the central axis onto the axis of rotation. The central axis of the strainer element preferably extends into an eccentric plane spaced apart perpendicularly from the axis of rotation by an eccentric distance. The eccentric distance is particularly preferably constant during operation.
In a preferred embodiment, the tumbling motion of the strainer element is a superimposed motion consisting of a circular path motion and a relative lifting motion, wherein the circular path motion and the relative lifting motion are phase-shifted with respect to each other. The relative lifting motion results from a skewed inclination of the central axis relative to the axis of rotation and the rotationally fixed arrangement of the strainer element. The strainer element is rotated about the axis of rotation on a circular path during operation. Due to the rotationally fixed arrangement, the strainer element rotates relative to the drive during a circuit on the circular path, wherein the orientation is substantially constant in a global frame of reference. The strainer element wall thereby describes a relative lifting motion with respect to a housing wall enclosing the strainer element. A minimum circumferential spacing between the strainer element wall and the enclosing housing wall is thereby shifted along the axis of rotation. The lifting motion promotes filtration and/or enables backflushing of the strainer element wall. The valve body is preferably inclined such that said body lags behind the rotation. A first end face of the strainer element disposed proximally to the drive thereby preferably lags behind a second end face of the strainer element opposite the first end face during a circuit on the circular path. The central axis of the strainer element preferably describes a cylindrical surface during operation. It can, however, also be preferable that the first end face of the strainer element precedes the second end face.
A phase shift between the circular path motion and the relative lifting motion preferably has a value in a range from 5° to 180°, preferably 45° to 135°, particularly preferably 90°. The phase shift is preferably selected such that a segment of the strainer element wall disposed proximally to the housing wall simultaneously sees the greatest acceleration and a maximum relative velocity of the lifting motion.
In a preferred refinement, the strainer element is coupled to the drive by means of a joint element. The joint element is particularly preferably disposed between the strainer element and the eccentric. The joint element is preferably torsionally rigid in design and enables tilting the central axis of the strainer element, so that said strainer element is substantially rotationally fixed about the central axis during the tumbling motion. Preferably, the joint element is at least partially made of an elastomer material.
In a preferred embodiment, the drive comprises a motor and a drive shaft extending into the housing and coupled to the at least one strainer element for rotationally driving the strainer element. Said drive shaft can be guided directly or indirectly into the housing. A gearbox is preferably disposed between the motor and the drive shaft. The motor can be implemented particularly as an electric motor.
In a further preferred embodiment, a press device is provided within the strainer element and is implemented for changing a distance from a strainer element wall during operation for pressing fibrous material against the strainer element wall. The press device is intended for compacting and dehydrating the fibrous material at the strainer element wall and for contributing in this manner to a type of “wringing” function and/or “squeezing” function. A greater degree of dehydrating the fibrous material can thereby be achieved.
In a preferred embodiment, the press device comprises a bar-shaped or ring-shaped press element. The longitudinal axis of the bar-shaped or ring-shaped press element is preferably aligned substantially parallel to the central axis of the strainer element, so that the bar-shaped or ring-shaped press element can extend substantially over the entire axial extent of the strainer element wall. It is thereby possible to achieve a pressing or wringing function along the entire axial length of the strainer element wall, and to achieve effective dehydrating of the fibrous material. It is thereby not necessary, but is preferable, that the bar-shaped or ring-shaped press element is cylindrical. There can also be embodiments wherein an oval cross section of the press element is advantageous.
It can thereby be provided that the press element is freely movable within the strainer element. The strainer element is moved, and thereby the press element is as well. If the press element is freely movable within the strainer element, said body is subjected to inertial forces and moves in the direction of the strainer element during the rotary motion of the strainer element.
Alternatively, the press element can be guided or stationary within the strainer element. The strainer element is moved and thereby the distance between the strainer element wall and the press element changes, so that a pressing or wringing function is achieved.
The press element is preferably fixed on a first side of the housing opposite the drive. For example, the press element can be screwed to the housing. Further adhesive, form-fit, and/or force-fit attachments are also preferable. In a particularly preferred embodiment, the housing comprises a cover, wherein the press element is fixed on the cover and can be used with the same at the separator device. It can be provided that the press element extends along the axis of rotation.
In a preferred refinement, the press element extends into the strainer element in a range from about 20% to 100%, preferably 50% to 100%, particularly preferably 70% to less than 100% of a length of the strainer element, measured between a first end face of the strainer element disposed proximally to the drive, and a second end face of the strainer element opposite the first end face. By extending the press element into the strainer element, a volume of the strainer element and/or a separating effect can be adjusted. A diameter of the press element is preferably selected such that contact between the press element and the strainer element is avoided when the strainer element is moved. The press element particularly preferably extends from the second end face to approximately just above a floor of the strainer element.
In a preferred embodiment, the second outlet is connected to the strainer element by means of a flexible discharge. The flexible discharge preferably allows rotating of the strainer element about the axis of rotation and is particularly preferably torsionally rigid in design. It can be provided that the flexible discharge fixes the strainer element rotationally about the central axis. To this end, the flexible discharge can be preferably rotationally fixedly connected to the housing. It should be understood that the flexible discharge can also comprise non-flexible elements.
The flexible discharge is preferably connected to the strainer element in a fully circumferentially sealing manner. Fibrous material then exits the strainer element into the flexible discharge and can reach the second outlet. The flexible discharge particularly preferably connects entirely to an end face of the strainer element. For example, the flexible discharge can be fitted over the strainer element and thus connected to the same. The flexible discharge is preferably releasably connected to the strainer element. A tube collar or a clamping ring can be provided for this purpose. It should be understood, however, that the flexible discharge can also be non-releasably connected to the strainer element.
The flexible discharge is preferably connected to a second end face of the strainer element opposite the first end face of the strainer element disposed proximally to the drive. The fibrous material is thus discharged via the second end face of the strainer element. Both the flexible discharge and the press element are particularly preferably disposed on the second end face of the strainer element.
In a preferred embodiment, the flexible discharge comprises a discharge hose connected at a first end to the strainer element. The first end of the discharge hose is preferably placed over the strainer element and fixed to the strainer element by means of a hose clamp. The flexible discharge preferably comprises at least two discharge hoses preferably uniformly distributed over the circumference of the strainer element. The flexible discharge can further preferably comprise a bellows, a spiral hose, and/or pipe segments joined in an articulated manner. The flexible discharge can further comprise one or more coupling elements, one or more cylindrical pipes, and/or one or more pipe elbows. The discharge hose particularly preferably opens into a discharge pipe connected to the second outlet.
A second end of the discharge hose is preferably connected to the housing for substantially rotationally fixing the strainer element. Fixing the second end of the discharge hose to the housing causes the discharge hose to be rotationally fixed, so that said hose cannot rotate about the longitudinal axis thereof extending between the first end and the second end. The discharge hose is preferably torsionally rigid in design, so that rotation of the strainer element connected to the first end of the discharge hose is prevented. It should be understood that the discharge hose can allow slight torsion about the longitudinal axis thereof, whereby the strainer element can perform slight rotary motions about the central axis thereof. A maximum rotation angle of the strainer element about the central axis thereof can be preferably adjusted by means of the torsional rigidity of the hose. Slight rotations of the strainer element about the central axis thereof can be advantageous, for example, for preventing solid material present in the wastewater from clogging. The discharge hose is also preferably bendable about the longitudinal axis thereof, so that said hose allows rotation of the strainer element about the axis of rotation. If the strainer element is moved along a circular path, then the first end can preferably follow the motion, wherein the second end is stationary. It can, however, also be preferable that the flexible discharge fixes the strainer element about the axis of rotation and the central axis and allows tilting of the central axis of the strainer element.
The housing preferably comprises a support element, wherein the discharge hose is attached to the support element. The support element can extend partially into a hollow space formed by the housing. The support element is particularly preferably implemented as a plate in the housing and comprises a pass-through channel for the fibrous material. A pipe segment of the flexible discharge can also preferably implement the support element or be connected to the support element. In a preferred refinement, the discharge hose can be connected to the housing by means of a rotary joint, so that said hose allows rotating of the strainer element about the central axis.
The press element is preferably disposed at least partially within the flexible discharge and forms a discharge channel with the flexible discharge. The press element preferably extends completely through the discharge hose. It can also be provided, however, that the press element runs substantially parallel to the flexible discharge. The discharge channel is preferably implemented as an annular channel. A cross-sectional flow area of the discharge channel is preferably less than a cross-sectional area of the strainer element. The discharge channel preferably allows circumferentially symmetrical discharge of the fibrous material out of the strainer element.
In a preferred embodiment, the inlet is connected to the interior of the strainer element by means of a flexible infeed. The flexible infeed allows rotation of the strainer element about the axis of rotation. The flexible infeed preferably also allows rotating about the central axis. The flexible infeed can also preferably fix the strainer element rotationally about the central axis thereof. The flexible infeed is particularly preferably implemented as substantially torsionally rigid.
In a preferred refinement, the flexible infeed is connected to the strainer element in a fully circumferentially sealing manner. For example, the flexible infeed can be fitted over the strainer element and thus connected to the same. It can also be provided, however, that the flexible infeed opens into the strainer element in a sealing manner.
The flexible infeed is preferably connected to a first end face of the strainer element disposed proximally to the drive. The flexible infeed is particularly preferably opposite the flexible discharge. By means of such an embodiment, uniform flow of the wastewater through the strainer element can be achieved. The first end face is particularly preferably disposed in a vertical direction below the second end face of the strainer element, so that the wastewater is fed into the strainer element from below. Discharging of the fibrous material is also preferably done from above. A gravity-powered discharge of the fibrous material from the strainer element is thereby prevented.
According to a preferred embodiment, the flexible infeed comprises at least one infeed hose. The flexible infeed can also comprise an infeed bellows, a spiral hose, or pipe segments joined in an articulated manner. The infeed hose is preferably bendable about the longitudinal axis thereof. The flexible infeed preferably comprises a first infeed hose and a second infeed hose, wherein the second infeed hose extends at least partially within the first infeed hose for forming an infeed channel. The infeed channel is preferably implemented as an annular channel. It can be provided that a drive shaft of the drive extends through the second infeed hose. It can thereby be advantageously prevented that one or more elements of the drive come into contact with wastewater. The first infeed hose and the second infeed hose can also be disposed adjacent to each other. The flexible infeed particularly preferably comprises a plurality of infeed hoses distributed uniformly at an end face of the strainer element. The flexible infeed preferably further comprises a manifold implemented for feeding in the wastewater to the infeed channel. The manifold is preferably implemented as a pipe elbow connected to the inlet.
It can be provided that the first infeed hose is fully sealingly connected to a cylindrical surface of the strainer element, and that the second infeed hose is sealingly connected to a step of the strainer element. The first infeed hose is preferably placed over the strainer element and fixed thereon. The second infeed hose sealingly connects to a step of the strainer element, wherein the strainer element preferably comprises one or more infeed openings disposed between the step and the cylindrical surface of the strainer element. In order to enable infeeding the wastewater in as circumferentially symmetrical a manner as possible, the infeed openings can also be implemented as segments of an annular gap.
In a preferred embodiment, the separator device comprises a feed pump for feeding the wastewater into the first strainer element under pressure. The housing is preferably closed, so that a pressure in the interior of the housing is greater than an ambient pressure. A pressure gradient preferably exists between the interior of the strainer element and the first outlet for the filtrate, so that the filtrate is pressed through the strainer element.
The first outlet preferably comprises a shut-off valve implemented for adjusting a first discharge pressure for the filtrate. The shut-off valve is preferably implemented as a ball valve, as a pinch valve, or as a gate valve. It can also be provided that the second outlet comprises a shut-off valve implemented for adjusting a second outlet pressure for the fibrous material. It should be understood that the shut-off valve can also be disposed upstream of the first outlet and fluidically connected to the first outlet. The shut-off valve can also be disposed downstream of the second outlet and fluidically connected to the second outlet
The first discharge pressure is preferably lower than the second discharge pressure. In this case, a pressure gradient between the interior of the strainer element and the first outlet is greater than a corresponding pressure gradient between the interior of the strainer element and the second outlet. A separation effect of the separator device can thereby be improved. Filtrate is thereby pressed through the strainer element wall by the pressure gradient. A ratio of the first discharge pressure to the second discharge pressure further influences a residual content of filtrate remaining in the fibrous material.
In a preferred embodiment, the separator device comprises an inlet pipe forming the inlet and extending into the interior of the strainer element substantially along the axis of rotation. The inlet pipe extends preferably substantially completely through the strainer element. If the strainer element, as described above, is preferably substantially vertically oriented, then in this case the inlet pipe extends preferably from the top to approximately just above the baseplate of the strainer element. In this case, the inlet pipe can form the press element. The diameter of the inlet pipe can be selected so that a sufficient wringing function is achieved. It should be understood that wringing out can also constitute pressing, preferably by applying force perpendicular to the strainer element. It is also conceivable that the inlet pipe be enclosed in a second sleeve, so that a sufficient diameter is achieved. Variation of the wall thickness of the inlet pipe can also be considered.
The invention further relates to a separator device for separating fibrous material from wastewater, having a housing comprising at least one inlet for wastewater, at least one first outlet for filtrate, and at least one second outlet for the fibrous material, and having at least one hollow strainer element disposed in the housing, the inlet opening being disposed in an intermediate space between the housing and the strainer element, and the first outlet being disposed in the interior of the strainer element, characterized in that the at least one strainer element is movably disposed in the housing and coupled to a drive for displacing the strainer element. A press element is preferably disposed in the intermediate space. With respect to advantageous embodiments of said separator device, reference is made to the entirety of the above description of the first consideration of the invention.
In a further embodiment of the invention, the drive comprises an oscillation gearbox for driving the strainer element in an oscillating manner. Both types of motion should be considered in general, that is, continuously rotating about the axis of rotation and oscillating. It is also conceivable that said two operating modes are performed alternately or according to a particular schema. When oscillating, a back-and-forth vibration of the liquid can be achieved within the strainer element, whereby fibrous material automatically accumulates on the inner surface of the strainer element. Particularly, simple backflushing is also thereby achieved. Thus, filtration always takes place under oscillation at the trailing side of the strainer element, while backflushing is performed at the leading side of the strainer element. Buildup of fibrous material at the strainer element and thus blocking of the strainer element can thus be prevented.
According to a preferred embodiment, at least two strainer elements are provided, particularly at least three, at least four, at least five. A preferred quantity has been determined to be a quantity of less than ten strainer elements. For example, four strainer elements present a good quantity for enabling efficient filtering of the liquid while nevertheless not leading to increased design effort. In such an embodiment, it is preferably provided that the at least two strainer elements are disposed so that the axis of rotation is outside of the strainer element. Preferably, however, all strainer elements have a common axis of rotation. That is, in the present embodiment the strainer elements rotate jointly about the common axis of rotation. An oscillating drive is particularly preferred for such embodiments. It is thereby also particularly suitable if a freely movable press element is disposed within each strainer element.
The strainer elements can thereby also be connected by means of flexible hoses for feeding in and removing liquid or sludge in such cases. This is particularly simple if the strainer elements are moved in an oscillating manner and do not continuous rotate in one direction.
The strainer element preferably has a mesh size of 10 μm to 300 μm. The mesh size is preferably in a range from 100-300 μm, preferably 150-250 μm. It is further preferable that the mesh size is in a range from 10 μm to 100 μm, preferably 10 μm to 50 μm. The exact mesh size can depend on the type of wastewater to be filtered, particularly from the objective of separating and the type of fibrous material. A mesh size in a range from approximately 300-100 μm is preferred for coarse separation and a mesh size in a range from 10-100 μm for fine separation of watery wastewater.
A plurality of strainer elements can also be placed concentrically one inside the other. The mesh size then preferably decreases from the inside to the outside. For example, an inner strainer element can have a mesh size in a range from approximately 300-100 m, and strainer element further outside can have a mesh size of approximately 10-100 μm.
In a second consideration of the invention, the object stated above is achieved by a method for separating fibrous material from wastewater, particularly using a separator device according to any one of the preferred embodiments of a separator device according to the first consideration of the invention, as described above.
The method preferably comprises at least the following steps: feeding wastewater carrying fibers into a strainer element; moving the strainer element; filtering wastewater at the strainer element; discharging filtrate out of an intermediate space between the strainer element and a housing; discharging fibrous material from the interior of the strainer element. The steps of the method for separating fibrous material are preferably performed at least partially simultaneously and/or continuously. The moving preferably comprises oscillation. It can also be provided that the displacing comprises a tumbling motion. The tumbling motion preferably induces a flow parallel to an axis of rotation and/or a flow about the central axis of the strainer element.
It should be understood that the separator device according to the first consideration of the invention and the method according to the second consideration of the invention have identical and similar sub-considerations, as are particularly set forth in the dependent claims. In this respect, reference is made to the entire above description of the separator device according to the first consideration of the invention.
A preferred embodiment of the method comprises the steps: filtering wastewater at a first segment of the strainer element trailing with respect to a direction of motion; and backflushing of the strainer element in a second segment of the strainer element leading with respect to the direction of motion. Said steps are preferably performed when the moving comprises oscillating. Permanent accumulation of fibrous material at the strainer element wall can be prevented, and dehydrated sludge having a high concentration of fibrous material can be discharged via the second outlet.
It is further preferable that the method comprises: pressing fibrous material by means of a press element against an inner side of the strainer element wall of the strainer element. In a preferred refinement of the method, the strainer element is rotationally fixed about the central axis.
Embodiments of the invention are described below using the drawings. Said drawings are not necessarily intended to depict the embodiments to scale; rather, the drawings are shown in schematic and/or slightly distorted form for explanatory purposes. With respect to supplements to the teachings directly discernible from the drawings, reference is made to the applicable prior art. It must thereby be considered that various modifications and changes relating to the shape and detail of an embodiment can be made without deviating from the general idea of the invention. The features of the invention disclosed in the description, in the drawings, and in the claims can be essential to the refinement of the invention individually and in any arbitrary combination. All combinations of two or more features disclosed in the description, the drawings, and/or the claims also fall within the scope of the invention. The general idea of the invention is not limited to the precise form or the detail of the preferred embodiments shown and described below or limited to a subject-matter that would be limited in comparison with the subject-matter claimed in the claims. Where dimensional ranges are indicated, values within the stated limits should also be disclosed as limit values and arbitrarily usable and claimable. For simplicity, identical reference numerals are used below for identical or similar parts or parts having identical or similar functions.
Further advantages, features, and details of the invention result from the below description of the preferred embodiments and from the drawings, which show:
According to
The housing 4 has an inlet 20 for wastewater 3. The inlet 20 is formed in the present embodiment example (
Once wastewater 3 has been fed through the inlet pipe 22 into the interior of the strainer element 6 by means of the pump 26, said wastewater is filtered by means of the strainer element wall 14, so that filtrate enters an intermediate space 9 between the housing wall 10 and the radially outer side of the strainer element 6. In order to remove the filtrate from the intermediate space 9, the housing 4 comprises a first outlet 30 for filtrate. The first outlet 30, in turn, is connected to a line 32 in which a pressure gage 33 and a shut-off valve 34 are placed. During operation, filtrate is typically removed at approximately 0.7 bar.
In order to remove the fibrous material 2 or the filter cake from the interior of the strainer element 6, the housing 4 comprises a second outlet 36, shown only schematically in
The separator device 1 further has a drive 40 comprising an electric motor 42 in the present embodiment example. The electric motor 42 in the present embodiment example (
The central axis A of the strainer element 6 is disposed offset to the axis of rotation R by an eccentric distance E. In this manner, it is achieved that the strainer element 6 is always moved perpendicular to the central axis A thereof when the drive shaft 44 is rotated, whereby movement of the liquid within the strainer element 6 and outside thereof in the intermediate space 9 is achieved. Said configuration can be seen particularly well in
In a similar manner, liquid in a trailing segment 6b of the strainer element wall 14 is pressed through the strainer element wall 14 from the inside to the outside and is thus filtered. In addition, due to the flow, compacting of the fibrous material 2 against the inner wall of the strainer element 6 can occur here, whereby the filtration is more efficient.
With reference to
By dimensioning the outer diameter of the inlet pipe 22 accordingly, said effect can be influenced in a targeted manner.
An embodiment example modified with respect to the above is shown in
A first difference in the separator device 1 according to the second embodiment example (
Due to the plurality of strainer elements 6 in the present embodiment example (
In a similar manner, the separator device 1 also comprises a plurality of second outlets 36, namely, exactly four, wherein each of the plurality of second outlets 36 is associated with a strainer element 6. The second outlets 36 in turn are connected to flexible hoses 68 extending into the interior of the particular strainer element 6, so that fibrous material 2 can be removed from the interior of each strainer element 6.
A further difference is present in the drive 40. Said drive in turn comprises an electric motor 42, in the present embodiment example (
The oscillating motion is shown in
According to a third embodiment (
The housing 4 in the third embodiment is substantially cylindrical in design and defines an interior space 8. A side wall 10 of the housing 4 is cylindrical in design and the housing 4 further comprises a floor 12 and a cover 74. With respect to
The drive 40 has an electric motor 42 connected to a drive shaft 44 by means of a belt drive 84. The drive shaft 44 is rotatably supported in the base frame 78 and in the drive segment 76 of the housing 4 by means of the bearings 46. The drive shaft 44 extends along an axis of rotation R through an opening 45 in the floor 12 and is connected to the eccentric 50. An imbalance of the drive shaft 44 caused by the eccentricity E of the eccentric 50 and the strainer element 6 is preferably compensated for by means of the balancing weights 79. The strainer element 6 comprises a bearing shell 88 here, rotatably supported on an eccentric lug 86 of the eccentric 50 by means of the rotatable bearings 90, implemented here in a fixed and floating arrangement. The fixed bearing 92 is implemented as a ball bearing and the floating bearing 94 as a cylindrical rolling bearing. It should be understood that the strainer element 6 can also be supported on the eccentric 50 by means of other forms of rolling bearings or by means of a plain bearing. The bearings 90 can also be implemented as a queued bearing arrangement. The eccentric 50 is connected to the drive shaft 44 such that the central axis A has an eccentric distance E from the axis of rotation R. If the drive shaft 44 is caused to rotate about the axis of rotation R by means of the electric motor 42 and the belt drive 84, then the strainer element 6 rotates on a circular path about the axis of rotation R. A radius of the circular path is determined by the eccentric distance E.
The housing 4 has an inlet 20 for wastewater 3 (not shown in
The inlet 20 can be connected to a hose or a line 24 in which a pump 26 is placed in order to pump wastewater 3 from a wastewater tank 28 to the inlet 20. Once wastewater 3 has been fed into the interior space 97 of strainer element 6 through the inlet 20, the pipe elbow 110, and the infeed channel 114, said wastewater 3 is filtered by means of the strainer element wall 14, so that filtrate enters an intermediate space 9 between the housing wall 10 and the radially outer side of the strainer element 6. In order to remove the filtrate from the intermediate space 9, the housing 4 comprises a first outlet 30 for filtrate (not shown in
In the third embodiment example, the separator device 1 comprises a press element 60 fixed on a second support element 120 of the housing 4 on a first side 118 of the housing opposite the drive. The press element 60 is implemented here as a hollow cylindrical element extending along the axis of rotation R for approximately 90% of a length of the strainer element 6, measured between the first end face 80 and the second end face 82, in the interior space 97 of the strainer element 6. If the strainer element 6 rotates about the axis of rotation R, a distance between a press element wall 61 of the press element 60 and the strainer element wall 14 varies, so that a “wringing effect” and/or a “pressing effect” reinforces the separating effect. Contact between the components is preferably avoided in order to minimize wear of the press element 60 and the strainer element 6. In order to scrape off solids adhering to the strainer element wall 14, however, it can be preferable that the strainer element 6 rubs against the press element 60. The press element wall 61 preferably comprises wiping elements to this end.
A flexible discharge 122 connects the second outlet 36 to the strainer element 6. To this end, the flexible discharge 122 comprises a discharge hose 124 sealingly connected at a first end 126 to the strainer element 6. The first end 126 of the discharge hose 124 is placed over the second end face 82 of the strainer element 6 and fixed thereon. A second end 128 of the discharge hose 124 is sealingly connected to the second support element 120, wherein the second support element 120 comprises a pass-through channel 130. The pass-through channel 130 guides the fibrous material 2 to the second outlet 36 (not shown in
A cross-sectional area of the discharge channel 132 extending substantially perpendicular to the axis of rotation R is preferably less than a cross-sectional flow section area of the infeed channel 114. It is also preferable that a cross-sectional flow area for the filtrate in the intermediate space 9 is greater than the cross-sectional area of the discharge channel 132. A flow resistance through the discharge channel 132 is thus preferably greater than a flow resistance in the intermediate space 9, whereby a separation effect can be reinforced.
The flexible discharge 122 and the flexible infeed 96 are particularly preferably disposed at opposite end faces of the strainer element 6. Particularly advantageous flow of the wastewater 3 can thereby be achieved. It can also be preferable, however, that an infeed and a discharge of the wastewater 3 take place on the same side of the strainer element 6.
According to a fourth embodiment (
The strainer shaft 52 of the strainer element 6 is received in the eccentric 50 at an angle and is rotatably supported by means of an angled bearing 134 (
The plan views of the separator device 1 according to the fifth embodiment shown in the
The flexible infeed 96 is implemented here as a first infeed hose 98 (
In a sixth embodiment of the invention, the central axis A of the strainer element 6 is inclined relative to the axis of rotation R. The central axis A of the strainer element 6 is thereby disposed in an eccentric plane EE spaced apart from the axis of rotation R by the eccentric distance E and parallel to the same. The central axis A of the strainer element 6 and the axis of rotation R are implemented skewed to each other and do not have a point of intersection (
According to the fifth embodiment example, the axis of rotation R is parallel to the side wall 10 of the housing 4. The axis of rotation R can also preferably be inclined relative to the housing 4 (
During operation, the strainer element 6 is moved on a circular path by means of the drive shaft 44, wherein the radius of the circular path corresponds to the eccentric distance E. During the circular path motion of the strainer element 6, said element rotates relative to the eccentric 50, so that an orientation of the strainer element 6 in the housing 4 remains substantially the same. A location of the reference point R1 is substantially constant, despite the circular path motion. It should be understood that the substantially constant location of the reference point R1 is relative to the orientation in the housing 4. The reference point R1 is not rotated about the central axis A here, but is moved along the circular path defined by the eccentric 50 and performs a relative lifting motion. An absolute value of a third circumferential wall distance D3, measured between the side wall 10 of the housing 4 and the strainer element wall 14, varies during operation due to the eccentric motion. The strainer element wall 14 of the strainer element 6 also performs a relative lifting motion, so that a relative minimum of the third circumferential wall distance D3 travels from the first end face 80 to the second end face 82 along a line on the strainer element wall 14 parallel to the central axis A. In
The relative lifting motion of the strainer element 6 is phase-shifted from the rotation of the strainer element 6 determined by the eccentric 50. It should be understood that the relative lifting motion may also be performed only partially by parts of the strainer element. The relative lifting motion preferably takes place in the region of the strainer element wall 14, wherein the relative height is constant at a centroid of the strainer element. Here the relative lifting motion lags the circular path motion by a value of approximately 90°. In
| Number | Date | Country | Kind |
|---|---|---|---|
| 20 2018 104 413.3 | Jul 2018 | DE | national |
The present application claims the benefit under 35 U.S.C. §§ 119(b), 119(e), 120, and/or 365(c) of PCT/EP2019/070630 filed Jul. 31, 2019, which claims priority to German Application No. 20 2018 104 413.3 filed Jul. 31, 2018.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2019/070630 | 7/31/2019 | WO | 00 |
