CA2312301A1 - Process and apparatus for metered dilution of fibrous material suspension in or in front of a material intake of a paper machine - Google Patents
Process and apparatus for metered dilution of fibrous material suspension in or in front of a material intake of a paper machine Download PDFInfo
- Publication number
- CA2312301A1 CA2312301A1 CA002312301A CA2312301A CA2312301A1 CA 2312301 A1 CA2312301 A1 CA 2312301A1 CA 002312301 A CA002312301 A CA 002312301A CA 2312301 A CA2312301 A CA 2312301A CA 2312301 A1 CA2312301 A1 CA 2312301A1
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- Prior art keywords
- backwater
- accordance
- fibrous material
- filter
- filter device
- Prior art date
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Links
- 238000000034 method Methods 0.000 title claims abstract description 47
- 239000002657 fibrous material Substances 0.000 title claims abstract description 43
- 239000000725 suspension Substances 0.000 title claims abstract description 43
- 239000000463 material Substances 0.000 title claims abstract description 36
- 238000010790 dilution Methods 0.000 title claims abstract description 8
- 239000012895 dilution Substances 0.000 title claims abstract description 8
- 239000000706 filtrate Substances 0.000 claims abstract description 48
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 30
- 238000007865 diluting Methods 0.000 claims abstract description 21
- 239000007787 solid Substances 0.000 claims description 16
- 239000012065 filter cake Substances 0.000 claims description 11
- 239000011343 solid material Substances 0.000 claims description 8
- 238000001914 filtration Methods 0.000 claims description 6
- 239000000835 fiber Substances 0.000 description 7
- 239000000945 filler Substances 0.000 description 2
- 239000013505 freshwater Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 101100352919 Caenorhabditis elegans ppm-2 gene Proteins 0.000 description 1
- 239000002671 adjuvant Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000005352 clarification Methods 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 238000009282 microflotation Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000012216 screening Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
- D21F1/00—Wet end of machines for making continuous webs of paper
- D21F1/08—Regulating consistency
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
- D21F1/00—Wet end of machines for making continuous webs of paper
- D21F1/66—Pulp catching, de-watering, or recovering; Re-use of pulp-water
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- Paper (AREA)
Abstract
Process and apparatus for metered dilution of fibrous material suspension in an apparatus including a material intake. The process includes treating a portion of backwater drained from the fibrous material suspension in a filter device, drawing off a cloudy filtrate arising in the filter device, forming diluting water from the cloudy filtrate, and metering the diluting water into the fibrous material suspension at a plurality of metering points in the material intake. The apparatus includes a material intake, a plurality of metering points coupled to the material intake, a fibrous material suspension supply coupled to the material intake, and a filter device coupled to receive a portion of backwater drained from the fibrous material suspension. In this manner, a cloudy filtrate is produced. The apparatus also includes a device to supply the cloudy filtrate to the plurality of metering points as diluting water.
Description
P19299.501 The present application claims priority under 35 U.S.C. ~ 119 of German Patent Application No. 199 28 488.1, filed on June 22, 1999, the disclosure of which is expressly incorporated by reference herein in its entirety.
1. Field of the Invention The invention relates to a process for the metered dilution of fibrous material suspension in or in front of a material intake of a paper machine. The metered diluting water is fed into the fibrous material suspension at a plurality of metering points, and the diluting water is derived from the backwater accumulating at a pulp concentration.
1. Field of the Invention The invention relates to a process for the metered dilution of fibrous material suspension in or in front of a material intake of a paper machine. The metered diluting water is fed into the fibrous material suspension at a plurality of metering points, and the diluting water is derived from the backwater accumulating at a pulp concentration.
2. piccussion of Background Information In paper production, it is known for processes of the type generally discussed above to be used in order to exert a controlled influence on the operation of a material intake. In particular, with the metered addition of diluting water at a plurality of points in the material intake, it is possible to modify the consistency of the fibrous material suspension contained therein and/or its speed of flow. As these procedures are generally known, they do not require description in greater detail. The diluting water required by this process can contain fibers or other solid matter only to a very limited degree, since disturbances will otherwise occur in the relatively sensitive metering devices. Furthermore, the outcome, which is to bring about a local dilution, is greatest when the water is clearest.
While the use of fresh water for this purpose would be technically advantageous, it is impractical due to the level of fresh water consumption. Instead, it is therefore customary to use backwater which accumulates in the paper machine. The backwater is often thoroughly purified of fibers and other solids with separating processes suitable to this end, e.g., microflotation or disk filters. This kind of filtrate, which arises in large quantities, is also highly suitable as diluting water for the described application, but comes at the price of the additional expense. The unfiltered backwater can be used with the fibrous material and fine matter contained in it, but in order to ascertain that the diluting water does not then contain disruptive parts, it must, as a rule, be purified once more in a sorting machine ("police filter").
P 19299.S01 The present invention provides a process with which diluting water can be made available for the above-noted purpose and in a particularly economical fashion.
In particular, the process includes treating the backwater in a filter device, and drawing off a cloudy filtrate that arises for use as diluting water.
The process according to the invention offers a very economical solution to the problem of preparing the required diluting water. It is known that backwater accumulating at a pulp concentration, e.g., in the wet section of the paper machine, contains a certain portion of fibers, fillers, and chemicals. In many modern paper factories, at least a large part of the backwater accumulating in the paper machine is clarified and returned as clear water at various points in the production circuit.
The clarification of backwater is advantageously performed with disk filters.
These devices are known in a number of applications, e.g., DE 38 29 177 Al, in which both primary (or cloudy) filtrate and clear filtrate accumulates. As is known, with the addition of a suitable adjuvant, a filter cake forms in disk filters which is suitable for retaining solids contained in the backwater. Thus, a filter process is fundamentally different from a screening process. In the beginning portion of a disk filter, i.e., at the place where a filter cake has not yet been able to form, the portion of fibers and fine material in the filtrate is relatively high.
Therefore, this so-called "cloudy filtrate" must be returned to the filtration process so as not to lower the quality of the clear filtrate. Moreover, if the cloudy filtrate is separately withdrawn and fed to the material intake as diluting water, the operation of the disk filter is substantially relieved, without disadvantages arising.
The present invention is directed to a process for metered dilution of fibrous material suspension in an apparatus including a material intake. The process includes treating a portion of backwater drained from the fibrous material suspension in a filter device, drawing off a cloudy filtrate arising in the filter device, forming diluting water from the cloudy filtrate, and metering the diluting water into the fibrous material suspension at a plurality of metering points in the material intake.
In accordance with a feature of the invention, the fibrous material suspension may be utilized in a paper machine.
According to another feature of the present invention, the filter device can include a disk filter with at least one filter disk divided into segments.
In accordance with another feature of the instant invention, the filter device may include P19299.S01 CA 02312301 2000-o6-Zo a filter press.
Further, the portion of the backwater to be treated in the filter device can be composed of backwater from the material intake. Further, the portion of the backwater to be treated can include second backwater of the apparatus. Still further, at least another portion of the backwater can be supplied to the fibrous material suspension.
In accordance with still another feature of the present invention, the cloudy filtrate may include a solid material content between about 100 ppm and S00 ppm. The at least a portion of the backwater to be treated in the filter device can have a solid material content which is at least about twice the solid material content of the cloudy filtrate.
According to an aspect of the invention, the at least a portion of the backwater to be treated in the filter device may have a solid material content of at least about 600 ppm.
Moreover, the at least a portion of the backwater may include a second backwater which is accumulated downstream, relative to a wire travel direction, of a first backwater, which comprises at least another portion of the backwater. Further, the process may include supplying the first backwater to a fibrous material supply. Also, the process can include mixing the first backwater with thick matter to form the fibrous material suspension, and supplying the fibrous material suspension to the material intake. The fibrous material suspension fed to the material intake may have a solids content of approximately 3.5% by wt. Still further, the first backwater may have a solids content of approximately 5000 ppm, and the second backwater has a solids content of approximately 2500 ppm.
According to a still further feature of the instant invention, the process can include supplying clear water to other portions of the apparatus. The clear water may have a solids content of approximately 50 ppm.
The cloudy filtrate can be formed at a beginning of a filtration process.
Further, the cloudy filtrate may have a solids content of between approximately 100 and 500 ppm.
The filter device may form a filter cake, and, before the filter cake is completely formed, the cloudy filtrate can be produced. After the filter cake is completely formed, the clear filtrate can be produced.
The present invention is also directed to an apparatus for metered dilution of a fibrous material suspension. The apparatus includes a material intake, a plurality of metering points coupled to the material intake, a fibrous material suspension supply coupled to the material intake, and a filter device coupled to receive a portion of backwater drained from the fibrous material suspension. In this manner, a cloudy filtrate is produced. The apparatus also includes a device P 19299. SO 1 to supply the cloudy filtrate to the plurality of metering points as diluting water.
In accordance with a feature of the invention, the filter device can include a disk filter with at least one segmented filter disk.
According to another feature of the present invention, the filter device can include a filter press.
In accordance with still another feature of the instant invention, another portion of the backwater can include a first backwater, and the portion of the backwater can include a second backwater which is accumulated downstream, relative to a wire travel direction, of the first backwater. The apparatus may further include a device for supplying the first backwater to the fibrous material suspension. The device for supplying the first backwater can include a mixing device adapted to mix the first backwater with thick matter, whereby the fibrous material suspension is formed.
According to yet another feature of the invention, the apparatus can include a device for supplying a clear filtrate from the filter device to other portions of the apparatus.
1 S Other exemplary embodiments and advantages of the present invention may be ascertained by reviewing the present disclosure and the accompanying drawing.
The present invention is further described in the detailed description which follows, in reference to a drawing by way of a non-limiting example of an exemplary embodiment of the present invention, and wherein:
The Figure schematically illustrates an exemplary embodiment of the process in accordance with the instant invention.
The particulars shown herein are by way of example and for purposes of illustrative discussion of the embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the present invention. In this regard, no attempt is made to show structural details of the present invention in more detail than is necessary for the fundamental understanding of the present invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the present invention may be embodied in practice.
While the Figure illustrates a part of a paper machine 3 with a material intake 1, it is noted that the process of the instant invention is not limited to any specific type of paper machine.
While the use of fresh water for this purpose would be technically advantageous, it is impractical due to the level of fresh water consumption. Instead, it is therefore customary to use backwater which accumulates in the paper machine. The backwater is often thoroughly purified of fibers and other solids with separating processes suitable to this end, e.g., microflotation or disk filters. This kind of filtrate, which arises in large quantities, is also highly suitable as diluting water for the described application, but comes at the price of the additional expense. The unfiltered backwater can be used with the fibrous material and fine matter contained in it, but in order to ascertain that the diluting water does not then contain disruptive parts, it must, as a rule, be purified once more in a sorting machine ("police filter").
P 19299.S01 The present invention provides a process with which diluting water can be made available for the above-noted purpose and in a particularly economical fashion.
In particular, the process includes treating the backwater in a filter device, and drawing off a cloudy filtrate that arises for use as diluting water.
The process according to the invention offers a very economical solution to the problem of preparing the required diluting water. It is known that backwater accumulating at a pulp concentration, e.g., in the wet section of the paper machine, contains a certain portion of fibers, fillers, and chemicals. In many modern paper factories, at least a large part of the backwater accumulating in the paper machine is clarified and returned as clear water at various points in the production circuit.
The clarification of backwater is advantageously performed with disk filters.
These devices are known in a number of applications, e.g., DE 38 29 177 Al, in which both primary (or cloudy) filtrate and clear filtrate accumulates. As is known, with the addition of a suitable adjuvant, a filter cake forms in disk filters which is suitable for retaining solids contained in the backwater. Thus, a filter process is fundamentally different from a screening process. In the beginning portion of a disk filter, i.e., at the place where a filter cake has not yet been able to form, the portion of fibers and fine material in the filtrate is relatively high.
Therefore, this so-called "cloudy filtrate" must be returned to the filtration process so as not to lower the quality of the clear filtrate. Moreover, if the cloudy filtrate is separately withdrawn and fed to the material intake as diluting water, the operation of the disk filter is substantially relieved, without disadvantages arising.
The present invention is directed to a process for metered dilution of fibrous material suspension in an apparatus including a material intake. The process includes treating a portion of backwater drained from the fibrous material suspension in a filter device, drawing off a cloudy filtrate arising in the filter device, forming diluting water from the cloudy filtrate, and metering the diluting water into the fibrous material suspension at a plurality of metering points in the material intake.
In accordance with a feature of the invention, the fibrous material suspension may be utilized in a paper machine.
According to another feature of the present invention, the filter device can include a disk filter with at least one filter disk divided into segments.
In accordance with another feature of the instant invention, the filter device may include P19299.S01 CA 02312301 2000-o6-Zo a filter press.
Further, the portion of the backwater to be treated in the filter device can be composed of backwater from the material intake. Further, the portion of the backwater to be treated can include second backwater of the apparatus. Still further, at least another portion of the backwater can be supplied to the fibrous material suspension.
In accordance with still another feature of the present invention, the cloudy filtrate may include a solid material content between about 100 ppm and S00 ppm. The at least a portion of the backwater to be treated in the filter device can have a solid material content which is at least about twice the solid material content of the cloudy filtrate.
According to an aspect of the invention, the at least a portion of the backwater to be treated in the filter device may have a solid material content of at least about 600 ppm.
Moreover, the at least a portion of the backwater may include a second backwater which is accumulated downstream, relative to a wire travel direction, of a first backwater, which comprises at least another portion of the backwater. Further, the process may include supplying the first backwater to a fibrous material supply. Also, the process can include mixing the first backwater with thick matter to form the fibrous material suspension, and supplying the fibrous material suspension to the material intake. The fibrous material suspension fed to the material intake may have a solids content of approximately 3.5% by wt. Still further, the first backwater may have a solids content of approximately 5000 ppm, and the second backwater has a solids content of approximately 2500 ppm.
According to a still further feature of the instant invention, the process can include supplying clear water to other portions of the apparatus. The clear water may have a solids content of approximately 50 ppm.
The cloudy filtrate can be formed at a beginning of a filtration process.
Further, the cloudy filtrate may have a solids content of between approximately 100 and 500 ppm.
The filter device may form a filter cake, and, before the filter cake is completely formed, the cloudy filtrate can be produced. After the filter cake is completely formed, the clear filtrate can be produced.
The present invention is also directed to an apparatus for metered dilution of a fibrous material suspension. The apparatus includes a material intake, a plurality of metering points coupled to the material intake, a fibrous material suspension supply coupled to the material intake, and a filter device coupled to receive a portion of backwater drained from the fibrous material suspension. In this manner, a cloudy filtrate is produced. The apparatus also includes a device P 19299. SO 1 to supply the cloudy filtrate to the plurality of metering points as diluting water.
In accordance with a feature of the invention, the filter device can include a disk filter with at least one segmented filter disk.
According to another feature of the present invention, the filter device can include a filter press.
In accordance with still another feature of the instant invention, another portion of the backwater can include a first backwater, and the portion of the backwater can include a second backwater which is accumulated downstream, relative to a wire travel direction, of the first backwater. The apparatus may further include a device for supplying the first backwater to the fibrous material suspension. The device for supplying the first backwater can include a mixing device adapted to mix the first backwater with thick matter, whereby the fibrous material suspension is formed.
According to yet another feature of the invention, the apparatus can include a device for supplying a clear filtrate from the filter device to other portions of the apparatus.
1 S Other exemplary embodiments and advantages of the present invention may be ascertained by reviewing the present disclosure and the accompanying drawing.
The present invention is further described in the detailed description which follows, in reference to a drawing by way of a non-limiting example of an exemplary embodiment of the present invention, and wherein:
The Figure schematically illustrates an exemplary embodiment of the process in accordance with the instant invention.
The particulars shown herein are by way of example and for purposes of illustrative discussion of the embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the present invention. In this regard, no attempt is made to show structural details of the present invention in more detail than is necessary for the fundamental understanding of the present invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the present invention may be embodied in practice.
While the Figure illustrates a part of a paper machine 3 with a material intake 1, it is noted that the process of the instant invention is not limited to any specific type of paper machine.
P19299.S01 However, paper machine 3 should include material intake 1 which is fed with a fibrous material suspension S that can be mixed in metered fashion with diluting water W via a plurality of metering points 2. After fibrous material suspension S has left material intake 1, it is immediately dewatered on the paper machine wire. In particular, a part of the water contained therein passes S through the paper machine wire as backwater, while the greatest portion of the paper fibers remains on the wire together with residual water and other materials, and is transported away. In the example shown here, two backwater qualities are separately handled, specifically a first backwater SW1 and a second backwater SW2. First backwater SW1 contains much more solid matter (e.g., fibers, fillers, etc.) than second backwater SW2.
The differences between the qualities of backwaters SW 1 (primary or cloudy filtrate) and SW2 (clear filtrate) have already been explained. The fibrous material suspension S fed to the material intake 1 is formed in a mixing pump 8 by mixing thick matter SO with first backwater SW1. A suspension formed in this way is generally known, and other similar methods of are conceivable. Second backwater SW2 can be introduced to a filter device 4.
1 S Filter device 4 can be, e.g., a disk filter, which may be particularly suited for implementation of the process. It is noted that the depiction of the exemplary embodiment is purely schematic and is intended to show only those functions that this disk filter fulfills insofar as they are important for the process according to the invention. Positioned in a suspension housing 6 is a rotor with at least one rotating filter disk 10. The filter disk is divided into a number of segments 5, which absorb the filtrate absorbed during filtering. The filter area of segments 5 mainly include a wire mesh, which becomes covered with fibrous material and other fine material by immersion in the suspension, i.e., second backwater SW2.
As already mentioned, at the beginning of the filtration process, while a filter cake is either not present or incomplete, an initial filtrate, i.e., cloudy filtrate TF, is obtained, which differs from clear filtrate KF that arises later in the filtration process, i.e., after the formation of the filter cake, in that it has a greater portion of solid particles and fibers. In order to remove both filtrates separately, i.e., cloudy filtrate TF and clear filtrate KF, a control head 7 is fixed in position in the center of the rotor. The filter cake positioned in the region of segments 5 is removed from this region as a coarse fraction GF before segments 5 are again immersed in the suspension being filtered. The technical design of such disk filters is known and does not need to be further described. Whereas clear filtrate KF is normally used as clear water at different points in the paper factory, cloudy filtrate TF according to the invention can be supplied to material intake 1 as diluting water W. A pump 9 can be employed to facilitate supplying cloudy filtrate TF to P19299.S01 material intake 1.
In an example of the process according to the exemplary embodiment, the following solid contents were measured:
15' backwater SW1: about 5000 ppm 2"d backwater SW2: about 2500 ppm cloudy filtrate TF: about 300 ppm clear filtrate KF: about SO ppm fibrous material suspension S: about 3.5% by wt.
It is noted that the foregoing examples have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the present invention. While the present invention has been described with reference to an exemplary embodiment, it is understood that the words which have been used herein are words of description and illustration, rather than words of limitation. Changes may be made, within the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of the present invention in its aspects. Although the present invention has been described herein with reference to particular means, materials and embodiments, the present invention is not intended to be limited to the particulars disclosed herein; rather, the present invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims.
The differences between the qualities of backwaters SW 1 (primary or cloudy filtrate) and SW2 (clear filtrate) have already been explained. The fibrous material suspension S fed to the material intake 1 is formed in a mixing pump 8 by mixing thick matter SO with first backwater SW1. A suspension formed in this way is generally known, and other similar methods of are conceivable. Second backwater SW2 can be introduced to a filter device 4.
1 S Filter device 4 can be, e.g., a disk filter, which may be particularly suited for implementation of the process. It is noted that the depiction of the exemplary embodiment is purely schematic and is intended to show only those functions that this disk filter fulfills insofar as they are important for the process according to the invention. Positioned in a suspension housing 6 is a rotor with at least one rotating filter disk 10. The filter disk is divided into a number of segments 5, which absorb the filtrate absorbed during filtering. The filter area of segments 5 mainly include a wire mesh, which becomes covered with fibrous material and other fine material by immersion in the suspension, i.e., second backwater SW2.
As already mentioned, at the beginning of the filtration process, while a filter cake is either not present or incomplete, an initial filtrate, i.e., cloudy filtrate TF, is obtained, which differs from clear filtrate KF that arises later in the filtration process, i.e., after the formation of the filter cake, in that it has a greater portion of solid particles and fibers. In order to remove both filtrates separately, i.e., cloudy filtrate TF and clear filtrate KF, a control head 7 is fixed in position in the center of the rotor. The filter cake positioned in the region of segments 5 is removed from this region as a coarse fraction GF before segments 5 are again immersed in the suspension being filtered. The technical design of such disk filters is known and does not need to be further described. Whereas clear filtrate KF is normally used as clear water at different points in the paper factory, cloudy filtrate TF according to the invention can be supplied to material intake 1 as diluting water W. A pump 9 can be employed to facilitate supplying cloudy filtrate TF to P19299.S01 material intake 1.
In an example of the process according to the exemplary embodiment, the following solid contents were measured:
15' backwater SW1: about 5000 ppm 2"d backwater SW2: about 2500 ppm cloudy filtrate TF: about 300 ppm clear filtrate KF: about SO ppm fibrous material suspension S: about 3.5% by wt.
It is noted that the foregoing examples have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the present invention. While the present invention has been described with reference to an exemplary embodiment, it is understood that the words which have been used herein are words of description and illustration, rather than words of limitation. Changes may be made, within the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of the present invention in its aspects. Although the present invention has been described herein with reference to particular means, materials and embodiments, the present invention is not intended to be limited to the particulars disclosed herein; rather, the present invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims.
Claims (26)
1. A process for metered dilution of fibrous material suspension in an apparatus including a material intake, the process comprising:
treating a portion of backwater drained from the fibrous material suspension in a filter device;
drawing off a cloudy filtrate arising in the filter device;
forming diluting water from the cloudy filtrate; and metering the diluting water into the fibrous material suspension at a plurality of metering points in the material intake.
treating a portion of backwater drained from the fibrous material suspension in a filter device;
drawing off a cloudy filtrate arising in the filter device;
forming diluting water from the cloudy filtrate; and metering the diluting water into the fibrous material suspension at a plurality of metering points in the material intake.
2. The process in accordance with claim 1, wherein said fibrous material suspension is utilized in a paper machine.
3. The process in accordance with claim 1, wherein the filter device comprises a disk filter with at least one filter disk divided into segments.
4. The process in accordance with claim 1, wherein the filter device comprises a filter press.
5. The process in accordance with claim 1, wherein the portion of the backwater to be treated in the filter device is composed of backwater from the material intake.
6. The process in accordance with claim 5, wherein the portion of the backwater to be treated comprises second backwater of the apparatus.
7. The process in accordance with claim 5, wherein at least another portion of the backwater is supplied to the fibrous material suspension.
8. The process in accordance with claim 1, wherein the cloudy filtrate comprises a solid material content between about 100 ppm and 500 ppm.
9. The process in accordance with claim 8, wherein the at least a portion of the backwater to be treated in the filter device has a solid material content which is at least about twice the solid material content of the cloudy filtrate.
10. The process in accordance with claim 1, wherein the at least a portion of the backwater to be treated in the filter device has a solid material content of at least about 600 ppm.
11. The process in accordance with claim 1, wherein the at least a portion of the backwater comprises a second backwater which is accumulated downstream, relative to a wire travel direction, of a first backwater, which comprises at least another portion of the backwater, and the process further comprises supplying the first backwater to a fibrous material supply.
12. The process in accordance with claim 11, further comprising:
mixing the first backwater with thick matter to form the fibrous material suspension; and supplying the fibrous material suspension to the material intake.
mixing the first backwater with thick matter to form the fibrous material suspension; and supplying the fibrous material suspension to the material intake.
13. The process in accordance with claim 12, wherein the fibrous material suspension fed to the material intake has a solids content of approximately 3.5% by wt.
14. The process in accordance with claim 11, wherein the first backwater has a solids content of approximately 5000 ppm, and the second backwater has a solids content of approximately 2500 ppm.
15. The process in accordance with claim 1, further comprising supplying clear water to other portions of the apparatus.
16. The process in accordance with claim 15, wherein the clear water has a solid content of approximately 50 ppm.
17. The process in accordance with claim 1, wherein the cloudy filtrate is formed at a beginning of a filtration process.
18. The process in accordance with claim 17, wherein the cloudy filtrate has a solids content of between approximately 100 and 500 ppm.
19. The process in accordance with claim 1, wherein the filter device forms a filter cake, and wherein, before the filter cake is completely formed, the cloudy filtrate is produced.
20. The process in accordance with claim 19, wherein, after the filter cake is completely formed, the clear filtrate is produced.
21. An apparatus for metered dilution of a fibrous material suspension, comprising:
a material intake;
a plurality of metering points coupled to said material intake;
a fibrous material suspension supply coupled to said material intake;
a filter device coupled to receive a portion of backwater drained from the fibrous material suspension, whereby a cloudy filtrate is produced; and a device to supply the cloudy filtrate to said plurality of metering points as diluting water.
a material intake;
a plurality of metering points coupled to said material intake;
a fibrous material suspension supply coupled to said material intake;
a filter device coupled to receive a portion of backwater drained from the fibrous material suspension, whereby a cloudy filtrate is produced; and a device to supply the cloudy filtrate to said plurality of metering points as diluting water.
22. The apparatus in accordance with claim 21, wherein the filter device comprises a disk filter with at least one filter disk divided into segments.
23. The apparatus in accordance with claim 21, wherein the filter device comprises a filter press.
24. The apparatus in accordance with claim 21, wherein another portion of the backwater comprises a first backwater, and the portion of the backwater comprises a second backwater which is accumulated downstream, relative to a wire travel direction, of the first backwater, and the apparatus further comprises a device for supplying the first backwater to the fibrous material suspension.
25. The apparatus in accordance with claim 24, wherein said device for supplying the first backwater comprises a mixing device adapted to mix the first backwater with thick matter, whereby the fibrous material suspension is formed.
26. The apparatus in accordance with claim 21, further comprising a device for supplying a clear filtrate from said filter device to other portions of the apparatus.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19928488.1 | 1999-06-22 | ||
| DE19928488A DE19928488C1 (en) | 1999-06-22 | 1999-06-22 | Process for the meterable dilution of the fiber suspension in or before a headbox of a paper machine |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2312301A1 true CA2312301A1 (en) | 2000-12-22 |
Family
ID=7912097
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002312301A Abandoned CA2312301A1 (en) | 1999-06-22 | 2000-06-20 | Process and apparatus for metered dilution of fibrous material suspension in or in front of a material intake of a paper machine |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP1063347B1 (en) |
| AT (1) | ATE301208T1 (en) |
| CA (1) | CA2312301A1 (en) |
| DE (2) | DE19928488C1 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102007042260B4 (en) | 2007-09-06 | 2012-09-27 | Leica Microsystems Cms Gmbh | Objective changer and a microscope |
| DE102011088063A1 (en) * | 2011-12-09 | 2013-06-13 | Voith Patent Gmbh | Clear filtrate treatment |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SE457772B (en) * | 1987-05-15 | 1989-01-30 | Harry Nilsson | FILTER FOR CONCENTRATION OF SUSPENSIONS |
| DE3829177A1 (en) * | 1987-09-16 | 1989-03-30 | Kufferath Andreas Gmbh | Disc thickener |
| FI971126A (en) * | 1997-03-18 | 1998-09-19 | Valmet Corp | Paper machine headbox dilution water treatment and circulation system |
| DE29812108U1 (en) * | 1998-07-09 | 1998-10-08 | Voith Sulzer Papiertechnik Patent GmbH, 89522 Heidenheim | Mixing and recirculation cycle |
-
1999
- 1999-06-22 DE DE19928488A patent/DE19928488C1/en not_active Expired - Fee Related
-
2000
- 2000-03-31 EP EP00106900A patent/EP1063347B1/en not_active Expired - Lifetime
- 2000-03-31 DE DE50010863T patent/DE50010863D1/en not_active Expired - Fee Related
- 2000-03-31 AT AT00106900T patent/ATE301208T1/en not_active IP Right Cessation
- 2000-06-20 CA CA002312301A patent/CA2312301A1/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| DE19928488C1 (en) | 2001-01-18 |
| ATE301208T1 (en) | 2005-08-15 |
| EP1063347A1 (en) | 2000-12-27 |
| DE50010863D1 (en) | 2005-09-08 |
| EP1063347B1 (en) | 2005-08-03 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued |