Water and air separation device for removing air from white water spray

Abstract

The present invention relates to a water and air separation system (100), an inlet portion (10) having a receiving inlet (11); A guide portion (20), The guide portion (20) A housing (24); A separation chamber (40); Entrance (21), a plurality of guide channels (12) for conveying the whitewater spray into a separation chamber; A liquid outlet (22); a gas outlet (23); The guide portion (20) further comprises a first separation plate (41) arranged to divide the separation chamber (40) into a first compartment (A) and a second compartment (B), whereby a connecting passage (46) is formed for passing the white water under the first separation plate (41) to the second compartment (B), thereby separating the white water from the air of the white water spray.

Description

Technical Field

[0001] The present invention relates to a water and air separation device for removing air from white water spray ejected from a forming wire in a forming section of a paper-making machine. The present invention also relates to a paper-making machine provided with such a water and air separation device.

Background Art

[0002] Paper, tissue, cardboard and other products are often manufactured from suspensions (such as cellulose in water). Such suspensions can be described as stock. The forming section of a paper-making machine for manufacturing tissue, paper or cardboard typically includes a headbox that injects stock between a loop of a forming wire (e.g., a porous wire mesh or cloth) driven around a lead roll and a loop of a fabric (e.g., a felt or another forming wire) typically driven around a forming roll. Due to the force applied to the stock (e.g., via the headbox, forming wire, fabric, or roll), water passes through the forming wire, capturing the suspended material on the wire and forming a web (e.g., cellulose) between the forming wire and the fabric. The water from the stock, generally called white water, is discharged through the forming wire. This ejection or spraying of the white water is usually collected and reused.

[0003] In order to reuse this spray of the discharged white water, it is necessary to remove a large amount of entrained air from the water. Typically, the spray is decelerated and collected to form a flow of liquid water in a so-called flume. The flume typically comprises a relatively long channel (often several meters in length) through which the water flows relatively slowly so that bubbles can rise to the surface before the water is reused. The flume and adjacent structures, which are intended to smooth the water and allow the bubbles to escape, are usually called the calming section.

[0004] Some paper machines are equipped with turbines to recover energy from the white water discharged from the molding section. While this is advantageous from an energy efficiency standpoint, it also has the drawback that a larger amount of air is mixed with the white water, making it more difficult to settle the white water in the flume of the settling section.

[0005] When handling white water spray, typically an inlet is provided to receive the white water spray from a forming section, optionally located between the inlet and the forming section, from a turbine. The white water then enters a guide section through multiple channels from the inlet, where it is decelerated and deflected to be discharged through an outlet to a sedation section. The deceleration provided in the guide section improves the sedation of the white water in the flume. There are several known prior arts that provide guide sections that pursue further improvement in white water sedation by separating air from the white water spray so that air removal in the sedation section is easier and more efficient. However, one problem with the prior art is that the separation of air is inefficient, or the design of the guide section even risks mixing air more completely with the white water, resulting in a less efficient and more cumbersome process of sedating the white water. This is particularly problematic when the turbine is used to recover energy from white water, as the turbine's operation generates a larger airflow, which draws white water into the inlet section, and the risk is that it will mix with the white water in the guide section.

[0006] Therefore, improvements are needed in this area. [Overview of the Initiative]

[0007] The object of the present invention is to eliminate, or at least minimize, the above-mentioned problems. This is achieved by the water and air separator described in the appended independent claims, and by a paper machine equipped with such a water and air separator.

[0008] This water and air separator is suitable for removing air from a white water spray ejected from a forming wire in the forming section of a paper machine. The water and air separator comprises an inlet section having an inlet for receiving the white water spray containing white water and air, and a guide section for guiding the white water from the inlet section to a settling section. The guide section comprises a housing, a separation chamber within the housing, and an inlet at the front of the housing. The guide section also comprises a plurality of guide channels extending from the inlet of the inlet section through the inlet of the guide section into the separation chamber. Each of the plurality of channels has a deflected downstream section to deflect the white water spray.

[0009] The guide section also includes a liquid outlet connected to the housing for draining white water from the separation chamber and a gas outlet connected to the housing for releasing air from the separation chamber. Furthermore, the guide section also includes a first separation plate extending downward into the separation chamber from the upper end and positioned to divide the separation chamber into a first compartment adjacent to the front and a second compartment adjacent to the rear side opposite the front. The first separation plate has a first height along the vertical axis that is lower than the height of the chamber along the vertical axis of the separation chamber, thereby forming a connecting passage for passing white water to the second compartment below the first separation plate, thereby separating the white water from the air in the white water spray.

[0010] The main advantage of the present invention is that the first separation plate is provided as described above, thereby significantly preventing air from entering the second compartment and allowing whitewater to enter the second compartment while the air remains in the first compartment. Since whitewater is denser than air in the whitewater spray, when it enters the separation chamber through the guide channel, the whitewater flows along the bottom of the guide channel, while the air flows over the whitewater instead. Thus, the separation plate functions to prevent air from significantly entering the second compartment, thereby preventing mixing of air and whitewater in the guide section. This allows air to be efficiently removed through the gas outlet, while the whitewater can exit through the liquid outlet and reach the settling section. This reduces the amount of air mixed with the whitewater, resulting in more efficient settling of the whitewater downstream of the guide section in the settling section.

[0011] Ideally, the first height of the first separation plate is 0.5 to 0.9 times the height of the chamber, preferably 0.6 to 0.7 times the height of the chamber. This achieves a connecting passage of appropriate height, thereby allowing the white water of the white water spray to proceed to the second compartment, while preventing the majority of the air in the white water spray that is not mixed with the white water from proceeding to the second compartment. This is advantageous in ensuring the separation of the white water that forms air.

[0012] Furthermore, the first separation plate may have a front surface facing the front of the separation chamber, the front surface extending at a first angle with respect to the vertical axis, the first angle being in the range of 5 to 45°, preferably 10 to 20°. This reduces wear and damage to the first separation plate due to white water contact, ensuring a longer lifespan and more reliable operation of the first separation plate.

[0013] The separation chamber may also have an average width from front to rear, and the second compartment may have a width of 0.05 to 0.6 times the average width of the separation chamber. This is beneficial in allowing for appropriate dimensions of the second compartment, thereby enabling the storage of white water therein.

[0014] The guide portion may also include a second separation plate positioned to extend downward from the upper end of the separation chamber into the first compartment, the second separation plate further extending along its front surface across the top of the guide channel outlet. This allows for more efficient guidance of the white water towards the passage below the first separation plate.

[0015] Ideally, the second separation plate is provided with multiple plate openings for introducing air through the second separation plate. This allows for more efficient separation of air from the whitewater by allowing air traveling over the guide channel to enter through the second separation plate, thus reducing the risk of this air mixing with the whitewater.

[0016] Furthermore, at least some of the multiple plate openings may be adjustable. This is advantageous because it allows for adjustment of the airflow inside the guide section by introducing more or less air into the opening of the second separation plate.

[0017] Ideally, the second separation plate has a second height along the vertical axis that is lower than the first height of the first separation plate. This facilitates the passage of white water beneath the second separation plate, resulting in reduced wear on the second separation plate.

[0018] The guide portion is a sealing plate positioned to extend downward from the upper side of the separation chamber into a first compartment, and may further comprise a sealing plate that joins with a second separation plate to form a third compartment defined by the second separation plate, the sealing plate, and preferably also by the upper end of the separation chamber, the third compartment may be in fluid communication with a gas outlet. This is advantageous in allowing air entering the third compartment to exit the guide portion through the gas outlet without risking further mixing of the air with white water.

[0019] Furthermore, the third compartment may be provided with a drain for discharging white water from the third compartment, and the drain is preferably located away from the entrance of the guide section. This allows any white water that may have ended up in the third compartment to be conveniently and reliably drained.

[0020] Ideally, the sealing plate further comprises a plurality of second plate openings for introducing air into the third compartment. This allows air from the first compartment to enter the third compartment as well, making the removal of air through the gas outlet more efficient.

[0021] Each guide channel may have a guide channel width in the upstream portion of its inlet, and the deflected downstream portion of each channel may be formed by a deflected portion of the guide channel wall in the downstream portion that is deflected laterally by at least the guide channel width. This ensures that the white water entering the guide channel across its entire width comes into contact with the deflected portion so that the white water is deflected. Therefore, the deflection is beneficial for more favorably directing the white water toward the liquid outlet.

[0022] Multiple guide channels may be formed by multiple plates spaced apart from each other. This is an efficient and reliable method to ensure that guide channels are formed for transporting the white water spray to the guide portion.

[0023] Alternatively, the guide channels may be formed by multiple pipes or tubes. This is an efficient and reliable method for providing guide channels and delivering the white water spray to the guide portion.

[0024] Ideally, the guide section housing further includes at least one additional inlet in a second compartment of the separation chamber to introduce additional white water into the separation chamber from outside the housing. This ensures that white water that cannot enter the receiving inlet of the inlet section and instead terminates at the top of the guide section housing is introduced into the guide section in a reliable and convenient manner.

[0025] Suitably, the turbine may be arranged to be connected to the receiving inlet of the inlet portion such that the white water spray passing through the turbine is received by the receiving inlet. This is advantageous for enabling the recovery of energy from the white water and helps to keep the energy consumption low in the production of paper, tissue or cardboard.

[0026] Also, the first separation plate may be attached to a rear plate extending from the lower end of the first separation plate to the upper end of the separation chamber, and the rear plate may be curved. This is advantageous for ensuring a stable flow of white water entering the second compartment and being deflected upward by the rear wall of the separation chamber, whereby, in order to control the turbulence of the white water and without causing excessive wear on the first separation plate, the white water can be induced downward again.

[0027] Furthermore, the separation chamber may have a first end and a second end, the first end being adjacent to the inlet, and the liquid outlet and the gas outlet may be closer to the second end than to the first end. The first separation plate may extend across the separation chamber from the first end towards the second end at least up to the gas outlet, or even further beyond the gas outlet. This is advantageous for preventing the white water from mixing with the air in the first compartment or the third compartment and making the separation of the white water and the air more reliable.

[0028] Suitably, the water and air separation device also comprises a settling portion connected to the liquid outlet of the guiding portion such that the white water discharged through the liquid outlet enters the settling portion. This is advantageous for enabling the settling of the white water passing through the guiding portion so that the air mixed in the white water can escape as bubbles from the settling portion.

[0029] The present invention also relates to a paper-making machine comprising at least one water and air separation device.

[0030] Many further advantages and benefits of the present invention will be readily apparent to those skilled in the art, considering the detailed description below.

[0031] The present invention will now be described in more detail with reference to the attached drawings. [Brief explanation of the drawing]

[0032] [Figure 1] A perspective view of a water and air separation apparatus according to a first embodiment of the present invention is disclosed. [Figure 2] The water and air separation device shown in Figure 1 in a plan view from the first end is disclosed. [Figure 3] Figure 1 shows a top-down perspective view of the water and air separation apparatus. [Figure 4] Figure 1 shows a top-down perspective view of the water and air separation apparatus. [Figure 5] Figure 1 discloses a plan view from above of the inlet portion of the water and air separation device. [Figure 6] Figure 1 discloses an overhead perspective view of the second end of the water and air separation device. [Figure 7] Figure 1 discloses an overhead perspective view of the first end of the water and air separation device. [Figure 8] Figure 1 discloses a perspective view of the water and air separation device from its second end. [Figure 9] Figure 1 discloses a perspective view of the second side of the water and air separation device from the lower end. [Figure 10] A plan view from the first end of the water and air separation device shown in Figure 1 is disclosed, illustrating the flow of water and air. [Modes for carrying out the invention]

[0033] All figures are schematic and not necessarily to scale, and generally show only the parts necessary to illustrate each embodiment, while other parts may be omitted or merely suggested. Any reference numerals appearing in multiple drawings refer to the same object or feature throughout the drawings unless otherwise indicated.

[0034] The water and air separation apparatus 100 according to the present invention will be described below with reference to various embodiments.

[0035] The water and air separation device 100 is a handling device suitable for receiving white water spray from the molding section of a paper machine during the manufacture of paper, cardboard, or tissue.

[0036] Machines and processes for manufacturing paper, cardboard, or tissue are well known in the art and will not be described in detail herein. A headbox generally injects stock into a nip formed in the forming section of a paper machine, and the white water from the stock, after passing through the nip, is discharged at high speed through the forming wire along with the airflow generated by the movement of rolls pressed against each other within the nip. The resulting white water spray, containing the white water mixed with air and the airflow, is captured by a water and air separator 100, as will be described in more detail below, and may also pass through a turbine just before entering the water and air separator 100 to recover kinetic energy from the white water.

[0037] White water is defined herein as water and particles from the stock that do not adhere to the molded fabric after the molded nip and are therefore discharged from the molded fabric and molded wire. Typically, the particles in white water are cellulose, but other particles and fragments from other materials that were present in the stock may also be present. As used herein, the term white water also includes air mixed with water to form a liquid that holds bubbles together with the air.

[0038] White water spray is defined herein as a stream of white water and air that is sprayed together from the molding section or flows together into the water and air separator 100. The air in the white water spray is unbound air that is carried together with the white water to form part of the liquid, but forms an air stream that is not sufficiently mixed with the white water; instead, it is two distinct fluids that flow together but each retains its distinct properties.

[0039] In the water and air separation apparatus of the present invention, the terms upstream and downstream are defined with respect to the flow of white water within the apparatus in use. This means that an upstream component is a component through which white water passes before reaching another downstream component.

[0040] Figure 1 discloses a water and air separator 100 according to a first embodiment of the present invention, comprising an inlet section 10 having an elongated receiving inlet 11 that is typically connected to the molding section of a paper machine when in use. The receiving inlet 11 preferably has a length that is at least the width of the web formed on the molding fabric and molding wire of the paper machine, so the length of the receiving inlet 11 may vary depending on the paper machine in which the water and air separator 100 is used. However, the main purpose of the receiving inlet 11 is to be able to receive as much of the white water spray ejected from the molding section as possible.

[0041] The water and air separator 10 also includes a guide section 20 connected to the inlet section 10, thereby transporting the white water spray entering the receiving inlet 11 into the separation chamber 40 inside the guide section 20. For this purpose, the guide section 40 has an inlet 21 on the front 26 of the housing 24, the inlet 21 is connected to the receiving inlet 11 of the inlet section 10, thereby enabling the white water to be transported into the separation chamber 40. Multiple guide channels 12 are provided extending from the receiving inlet 11 through the inlet 11 of the guide section 20 into the separation chamber 40, each guide channel having a deflected downstream section 142 that deflects the white water spray toward a liquid outlet 22 through which the white water is discharged from the guide section 20. Preferably, the liquid outlet 22 is connected to a settling section 30 as shown in Figure 1, but in some embodiments, the liquid outlet 22 may instead be connected to another component for receiving the white water, such as a pipe, conduit, or any other suitable component.

[0042] The guide channel is defined by a guide channel wall 13, which includes a deflected downstream portion 142, as will be described in more detail below in the first embodiment (see Figure 5).

[0043] The guide section 20 also includes a gas outlet 23 for removing air from the guide section 20 and is appropriately connected to an exhaust chimney 231 or other channel or conduit for transporting air from the guide section 20 in a reliable and convenient manner.

[0044] The guide portion 20 also includes a first separation plate 41 extending downward within the separation chamber 40 from the upper end 28. In some embodiments, the first separation plate 41 may be attached to the inner wall of the housing 24, in other embodiments it may be integrated with the housing 24, or it may be attached to another part of the guide portion 20, as long as the first separation plate 41 can extend into the separation chamber 40. The first separation plate 41 is elongated and extends from a first plate end 411 of the first end 201 of the separation chamber 40 toward a second end 202 of the separation chamber 40. In some embodiments, the first separation plate 41 may extend entirely to the second end 202, in other embodiments the separation plate 41 may instead have an end 412 that is separated from the second end 202. The first end 201 is the upstream end of the separation chamber 40 between the front 26 and the rear 27. The second end 202 is the downstream end of the separation chamber opposite to the first end 201. Therefore, the first end 201 is closer to the inlet 21 than the second end 202.

[0045] In the first embodiment shown in Figure 1, the second separation plate 44 is also provided inside the separation chamber 40 and is configured to extend from the guide channel 12 across the outlet 15 and along the inlet 21. In this embodiment, a sealing plate 45 is also attached to the lower end of the second separation plate 44, and the second separation plate 44 and the sealing plate 45 are each attached to the upper end 28 of the separation chamber 40, similar to the first separation plate 41.

[0046] The water and air separator 100 also includes at least one, preferably more, additional inlets 25 through which white water spray that was not captured by the receiving inlet 11 but instead reached the upper surface of the housing 24 can be introduced into the separation chamber 40.

[0047] Figure 2 discloses the water and air separator 100 as seen from the first end 201, showing a first separation plate 41 extending into the interior of the separation chamber 40 to separate a first compartment A and a second compartment B. The first compartment A is adjacent to the inlet 21 of the front 26, while the second compartment B is adjacent to the rear 27 on the opposite side of the front 26. A connecting passage 46 is formed between the first compartment A and the second compartment B, beneath the first separation plate 41, allowing white water to enter the second compartment B. A gas outlet 23 is operably connected to at least the first compartment A so that air can flow from the first compartment A to the gas outlet 23.

[0048] The first separation plate 41 has a front surface 42 facing the front surface 26 of the guide portion 20 and is positioned at a first angle α with respect to the vertical axis V. The first angle α is in the range of 5 to 45°, preferably 10 to 20°. This is to provide sufficient strength to the first separation plate 41 so as to reduce or minimize damage by white water entering the inlet 21 and hitting the front surface 42. The first angle α may vary within the above range and may be adjusted considering the flow direction of white water as it exits the guide channel 12 so that as much white water as possible enters the connecting passage 46, and preferably without hitting the front surface 42 of the first separation plate 41. For this purpose, it is also appropriate that the first height h1 of the first separation plate 41 in the vertical direction along the vertical axis V is in the range of 0.5 to 0.9 times the chamber height ch, preferably 0.6 to 0.7 times the chamber height ch.

[0049] The vertical axis V is the axis that is vertical when the guide portion 20 is in a position with its lower surface 29 facing downward, that is, the axis that is substantially vertical when the guide portion is configured to be used in connection with a paper machine.

[0050] In the first embodiment, the first separation plate 41 is attached to a rear plate 43 that extends from the lower end 413 of the first separation plate 41 to the upper end 28 of the separation chamber 40. In some embodiments, the first separation plate 41 and the rear plate 43 may be integrated, or they may comprise a single structure having a front surface molded as the front surface 42 of the first separation plate 41 in Figure 1 and a rear surface molded as the rear plate 43 in Figure 1. Other designs of the first separation plate 41 are also possible within the scope of the present invention.

[0051] The rear plate 43 is appropriately curved so that the white water, which strikes the rear surface 27 of the separation chamber 40 and is deflected upward toward the upper end 28, is then guided downward toward the lower surface 29 along the curved rear plate 43. This allows for handling of the white water in a way that reduces wear on the first separation plate 41. Preferably, the lower end 413 of the first separation plate 41 is also curved or inclined toward the rear surface 27, thereby guiding the white water further downward toward the rear surface 27.

[0052] As shown in Figure 2, one or more additional inlets 25 are provided at the top of the second compartment B so that additional white water not present in the water and air separator 100 through the receiving inlet 11 can be introduced into the second compartment B. Preferably, the additional inlet(s) 25 are positioned at a certain angle to the direction of the white water flow in the second compartment B so that the white water flow already present inside can draw the white water into the second compartment B. The additional inlets may have covers to prevent undesirable discharge from the separation chamber 40 through the additional inlet 25. In the first embodiment shown herein, the additional inlet 25 is inclined to have an opening to the separation chamber facing the liquid outlet 22.

[0053] The separation chamber 40 has an average width w from the front 26 to the rear 27. a The second section B has an average width w from the connecting passage 46 to the rear surface 27. a The average second plot width is 0.05 to 0.6 times the first plot width. B In various embodiments of the present invention, the average second section width w of the second section B B This can be adapted according to the dimensions of the guide portion 20 and the entire water and air separator 100, as well as the magnitude of the white water flow in which the water and air separator 100 is used. In some embodiments, the average second compartment width w of the second compartment B B The main criterion for determining this is that the flow of white water entering the separation chamber 40 can enter the second compartment and flow in an appropriate manner, as described below with reference to Figure 10.

[0054] In the first embodiment shown in Figure 2, a second separation plate 44 is also provided, positioned to protrude from the upper end 28 of the first compartment A. Preferably, the second separation plate 44 is positioned connected to the downstream end of the guide channel 12 and covers the upper part of the inlet 21, i.e., the outlet 15 from the guide channel 12, such that the white water spray hitting the second separation plate 44 is deflected downward in the first compartment A of the separation chamber 40. This is advantageous in ensuring that the flow of white water is guided into the connecting passage 46 to the second compartment B, and for this purpose, it is also advantageous that the second separation plate 44 has a second height h2 along the vertical axis V that is lower than the first height h1 of the first separation plate 41. It is also advantageous that the second separation plate 44 is at a second angle β with respect to the vertical axis V, and that the second angle β is in the range of 10 to 60°, preferably 30 to 50°. It is also advantageous if the second angle β is greater than the first angle α such that the white water is efficiently deflected downward toward the connecting passage 46 beneath the first separation plate 41. By positioning the second separation plate 44 at the second angle β, the white water in contact with the second separation plate 44 is deflected downward into the separation chamber 40, preventing turbulence caused by white water otherwise flowing upstream toward the inlet 10.

[0055] The second separation plate 44 extends from the upper end 28 of the separation chamber 40 and is connected to a sealing plate 45 that is joined to the second separation plate 44 at its lower end 442. The second separation plate 44 and the sealing plate 45 may be made from two separate plates joined to each other by any suitable means, or instead from a single structure, or integrated with the housing 28, or designed in any other suitable way. A third compartment C is formed defined by the second separation plate 44 and the sealing plate 45. In some embodiments, the third compartment C may also be defined by the upper end 28 of the separation chamber 40, but in other embodiments, the third compartment C may instead be connected at its upper end to an elongated gas outlet or any other space or conduit that can transport air. The third compartment C is also arranged in fluid communication with the gas outlet 23 so that air in the third compartment C can be transported from the guide portion 20 through the gas outlet 23.

[0056] Figures 3 and 4 disclose the water and air separator 100 from above to more clearly show both the channel wall 13 and the guide channel 12 defined by the second separation plate 44 and sealing plate 45. In this first embodiment, the second separation plate 44 has a plurality of plate openings 441 through which the white water spray, particularly the air of the white water spray, can enter the third compartment C from the guide channel 12. The sealing plate 45 also has a plurality of second plate openings 451 through which the air of the white water spray in the first compartment A can enter the third compartment C. In some embodiments, at least the plate opening 441, and optionally the second plate opening 451, are adjustable by, for example, a plate portion whose opening is not movable along the second separation plate 44 and optionally not movable along the sealing plate 45, or by other plate portions having a matching opening that is movable to be fully open, fully closed, or partially open, such that the opening of the plate portion coincides with the opening of the second separation plate 44 and optionally coincides completely, entirely, or partially with the opening of the sealing plate 45. Also, in some embodiments, all of the plate openings 441, 451 may be adjustable, while in other embodiments, all of the plate openings 441, 451 are adjustable. In some embodiments, either or both of the second separation plate 44 or the sealing plate 45 may lack an opening so that airflow is directed through either the second separation plate 44 or the sealing plate 45 to the third compartment C, or so that airflow is retained within the first compartment A.

[0057] The gas outlet 23 is operably connected to both the first compartment A and the third compartment C to form a fluid connection through which air can flow, although in some embodiments, the gas outlet 23 can instead be in fluid communication with only the first compartment A. In embodiments that include both the first compartment A and the third compartment C, the first compartment A can also be in fluid communication with the gas outlet 23 via the third compartment C.

[0058] Figures 3-4 disclose a guide channel 12 located inside or connected to a separation chamber 40, having a channel wall 13 and a deflected downstream portion 142 at the downstream end of the guide channel 12. In a first embodiment, the guide channel 12 is made of a plurality of plates spaced apart to form the channel wall 13. The plurality of plates may be arranged parallel to each other, or in any other way, as long as the guide channel 12 is formed so that the white water spray can pass through the separation chamber 40 along the guide channel 12. In some embodiments, the plurality of plates may be arranged essentially vertically, i.e., parallel to the vertical axis V, but in other embodiments, the plurality of plates may instead be arranged at a certain angle to the vertical axis V. The plurality of plates may also be flat or curved and may form a channel having a rectangular, triangular, or circular cross-section, or a honeycomb cross-section, or any other suitable shape. In some embodiments, the guide channel 12 may instead be formed by pipes or tubes arranged together to form a plurality of guide channels 12.

[0059] In the first embodiment, the guide channels 12 are arranged side by side, but it is advantageous that the guide channels 12 do not overlap each other. This has the advantage that the guide channels 12 are elongated vertically so that, due to the different densities of the white water and air, the white water spray can flow along the guide channels 12 with white water near the bottom of the guide channels 12 and free air from the white water spray above the white water. This is particularly advantageous for improving the passage of white water into the connecting passage 46 and preventing air from continuing into the second compartment B.

[0060] Figure 5 discloses the inlet portion 10 from above, more clearly showing the guide channels 12 and the channel walls 13 that define them. Each of the guide channels 12 has a channel width cw in the upstream portion 131, and in some embodiments the channel width cw is the same for each of the guide channels 12, but in other embodiments the channel width cw may instead vary such that some guide channels 12 are wider than others. Also in some embodiments the channel width cw may be constant along one guide channel 12 from the upstream portion 131 to the downstream portion 141, but in other embodiments the channel width cw of the guide channels 12 may instead vary.

[0061] In the downstream section 141, a deflected downstream section 142 is formed, in which at least one of the guide channel walls 13 is deflected, i.e., it advances in a direction that forms a certain angle with respect to the guide channel wall 13 of the upstream section 131. The purpose of the deflected downstream section 142 is to deflect the flow of the white water spray so that it is directed toward the rear surface 27 at a certain angle, rather than hitting the rear surface 27 perpendicular to the wall of the rear surface 27. This is advantageous for settling the white water spray and directing it toward the liquid outlet 22, as this facilitates the discharge of white water through the liquid outlet 22 and improves the settling of white water in the subsequent settling section 30 downstream of the guide section 20.

[0062] The deflected downstream portion 142 of the guide channel wall is configured to deflect by a distance d in the lateral direction, i.e., perpendicular to the longitudinal direction which is also the flow direction of the upstream portion 131 of the guide channel 12, and it is advantageous that this distance d is greater than or equal to the channel width cw of the guide channel 12. This has the advantage of ensuring that the overall flow of the white water spray, particularly the flow of the white water, is deflected. The deflected downstream portion 142 of the guide channel wall 13 may be integrated with the rest of the guide channel wall 13, or it may be formed by a separate section 14 fastened to the upstream portion of the guide channel wall 13. While it is advantageous to ensure the strength of the guide channel wall 13 to avoid joining along the length of the guide channel wall 13, in some embodiments it is also advantageous to provide a material for the deflected downstream portion 142 that has higher strength than the upstream portion of the guide channel wall 13 so that it can withstand the force of the white water hitting the deflected downstream portion 142.

[0063] As can be seen in Figures 3 to 5, the gas outlet 23 and the first separation plate 41 are positioned relative to each other such that the end 412 of the separation plate 41 is closer to the second end 202 of the guide portion 20 than the gas outlet 23, or at least the end 412 of the separation plate 41 is closer to the second end 202 as the gas outlet 23. This is advantageous in ensuring that white water from the second compartment B does not enter the gas outlet 23. This is shown more clearly in Figure 6, where the gas outlet 23 is shown in relation to the first separation plate 41 in particular.

[0064] Figure 7 discloses a second separation plate 44 having a plate opening 441 and a sealing plate 45 that together form a third compartment C. The first compartment A is defined and shown by the inlet 21, the second separation plate and sealing plate, and the first separation plate 41 and the lower end 29 of the separation chamber 40. Furthermore, Figure 7 discloses a second compartment B defined by the rear plate 43, the rear surface 27, and the lower end 29. As also shown in Figures 3-5 and 6, each of the first, second, and third compartments A, B, and C extends from the first end 201 of the guide portion 20 to the second end 202 of the guide portion 20 so that elongated compartments are formed through which the white water spray is transported to the liquid outlet 22 and the gas outlet 23. During use, the second compartment B mainly holds white water mixed with air, the third compartment C mainly holds air, and the first compartment A holds both white water and air. When the white water spray enters the water and air separator 100, some air is mixed with the white water, and some airflow forms part of the white water spray, however, some of the white water spray is not mixed with the white water so as to prevent the separation of the white water and the airflow. The design of the separation chamber 40 within the guide section 20 separates the airflow of the white water spray from the white water and the air mixed with the white water. This helps to remove the majority of the total amount of air present in the white water spray, and since separating the air mixed in the white water from the white water itself is only necessary in the settling section 30, it makes the separation in the settling section 30 easier and more efficient. Thus, while many guide sections in the prior art actually provide more complete mixing so that the white water contains more air after passing through the guide section than before, the present invention can remove the large amount of air in the white water spray that is not mixed with the white water itself.

[0065] Figure 8 discloses the inlet portion 10 and guide portion 20 from the second end 202, and in particular shows the configuration of the first separation plate 41 and the second separation plate 44 having first, second, and third compartments A, B, and C. Figure 8 also discloses a drain 47 from the third compartment C that allows white water that has entered the plate opening 441 or the second plate opening 451 to be discharged from the third compartment C.

[0066] Figure 9 also discloses a water and air separator 100 from the second end 202 of the guide portion 20, showing both the drain 47 and the gas outlet 23 more clearly. It is advantageous that the drain 47 be located near or at least equal to the distance of the second end 202 compared to the gas outlet 23, so that the fluid is discharged from a downstream third compartment C where the air is removed from the guide portion 20.

[0067] Figure 10 discloses a water and air separation device 100 according to a first embodiment, in which the flow of water is indicated by arrows and the flow of air by dashed arrows. In some embodiments, a turbine 60 is also provided, which may be positioned connected to the receiving inlet 11 so that the white water spray that has passed through the turbine 60 can enter the receiving inlet 11.

[0068] The white water flows along the bottom of each guide channel 12 and enters the separation chamber 40 near its lower end 29. After passing through the connecting passage 46, the white water is deflected upward along the rear wall 27 and guided downward along the curved side of the first separation plate 41. At the same time, the air of the white water spray passes over the top of each guide channel 12, with some air entering the third compartment C through the plate opening 441, while some air instead enters the first compartment A, is deflected upward along the first separation plate 41, and enters the third compartment C through the second plate opening 451. There may also be a small amount of air that enters and remains in the first compartment A, or enters the third compartment C through the second plate opening 451 near the second end 202 of the guide section 20.

[0069] In some embodiments, air may be biased to exit the guide section 20 through the gas outlet 23 by air transport means such as a fan connected to the gas outlet 23 or further inside the exhaust pipe or conduit 231. However, in other embodiments, air can instead exit the guide section 20 without being forced by air transport means, and instead, further white water spray can flow in by passing through the inlet section 10 into the separation chamber 40.

[0070] It should be noted that the features from the various embodiments described herein can be freely combined unless such combination is explicitly stated to be inappropriate.

Claims

1. A water and air separation device (100) in the molding section of a paper machine, which removes air from the white water spray ejected from the molding wire, An inlet section (10) having an inlet (11) for receiving a white water spray containing white water and air, A guide portion (20) for guiding the white water from the inlet portion to the settling portion, Equipped with, The aforementioned guide portion (20) Housing (24) and The separation chamber (40) within the housing, The entrance (21) on the front (26) of the housing, A plurality of guide channels (12) extending from the receiving inlet (11) of the inlet portion (10) through the inlet (21) of the guide portion (20) into the separation chamber (40), and transporting the white water spray into the separation chamber, each of which has a deflected downstream portion (142) for deflecting the white water spray, A liquid outlet (22) connected to the housing (24) for discharging white water from the separation chamber, The separation chamber is provided with a gas outlet (23) connected to the housing (24) for releasing air, The guide portion (20) further comprises a first separation plate (41) which extends downward into the separation chamber (40) from the upper end (28) of the separation chamber (40) and is arranged to divide the separation chamber (40) into a first section (A) adjacent to the front surface (26) and a second section (B) adjacent to the rear surface (27) opposite to the front surface (26), wherein the first separation plate (41) has a first height (h) along the vertical axis (V) that is lower than the chamber height (ch) of the separation chamber (40) along the vertical axis. １ A water and air separation device (100) having a connecting passage (46) for passing white water to the second compartment (B) below the first separation plate (41), thereby separating the white water from the air of the white water spray.

2. The first height (h) of the first separation plate (41) １ The water and air separation apparatus according to claim 1, wherein the height of the chamber (ch) is 0.5 to 0.9 times the height of the chamber (ch).

3. The water and air separation apparatus according to claim 1 or 2, wherein the first separation plate (41) has a front surface (42) facing the front surface (26) of the separation chamber (40), the front surface (42) extends at a first angle (α) with respect to the vertical axis (V), and the first angle (α) is in the range of 5 to 45°.

4. The separation chamber (40) has an average width (w) from the front surface (26) to the rear surface (27). ａ ) and the second compartment (B) has the average width (w) of the separation chamber (40). ａ The average second plot width (w) is 0.05 to 0.6 times the width of the first plot. Ｂ A water and air separation apparatus according to claim 1 or 2, having )

5. The water and air separation apparatus according to claim 1 or 2, wherein the guide portion (20) further comprises a second separation plate (44) positioned to extend downward from the upper end (28) of the separation chamber (40) into the first compartment (A).

6. The water and air separation apparatus according to claim 5, wherein the second separation plate (44) is provided with a plurality of plate openings (441) for introducing air through the second separation plate (44).

7. The water and air separation apparatus according to claim 6, wherein at least some of the plurality of plate openings (441) are adjustable.

8. The second separation plate (44) is at the first height (h) of the first separation plate (41). １ A second height (h) along the vertical axis (V) that is lower than (h) ２ The water and air separation apparatus according to claim 5, having )

9. The water and air separation apparatus according to claim 5, wherein the guide portion (20) is a sealing plate (45) disposed to extend downward from the upper end (28) of the separation chamber (40) into the first compartment (A), and the sealing plate (45) is joined to the second separation plate (44) to form a third compartment (C) defined by the second separation plate (44) and the sealing plate (45), and the third compartment (C) is in fluid communication with the gas outlet (23).

10. The water and air separation apparatus according to claim 9, wherein the third compartment (C) is provided with a drain (47) for discharging white water from the third compartment (C).

11. The water and air separation apparatus according to claim 9, wherein the sealing plate (45) further comprises a plurality of second plate openings (451) for introducing air into the third compartment (C).

12. The water and air separation apparatus according to claim 1 or 2, wherein each of the guide channels (12) has a guide channel width (cw) in the upstream portion (131) of the inlet portion (10), and the deflected downstream portion (141) of each channel (12) is formed by a deflected portion (14) of the guide channel wall (13) of the downstream portion (141) which is deflected laterally by at least the guide channel width (cw).

13. The water and air separation apparatus according to claim 1 or 2, wherein the plurality of guide channels (12) are formed by a plurality of plates arranged at intervals from one another.

14. The water and air separation apparatus according to claim 1 or 2, wherein the plurality of guide channels (12) are formed by a plurality of pipes or tubes.

15. The water and air separation apparatus according to claim 1 or 2, wherein the housing (24) of the guide portion (20) further comprises at least one additional inlet (25) in the second compartment (B) of the separation chamber (40) for introducing additional white water into the separation chamber (40) from outside the housing (24).

16. The water and air separation apparatus according to claim 1 or 2, further comprising a turbine (60) positioned connected to the receiving inlet (11) of the inlet portion (10), wherein a white water spray passing through the turbine (60) is received by the receiving inlet (11).

17. The water and air separation apparatus according to claim 1 or 2, wherein the first separation plate (41) is attached to a rear plate (43) that extends from the lower end (413) of the first separation plate (41) to the upper end (28) of the separation chamber (40), and the rear plate (43) is curved.

18. The water and air separation apparatus according to claim 1 or 2, wherein the separation chamber (40) has a first end (201) and a second end (202), the first end (201) is adjacent to the inlet (21) between the front (26) and the rear (27) that is upstream of the second end (202), the liquid outlet (22) and the gas outlet (23) are closer to the second end (202) than to the first end (201), and the first separation plate (41) extends across the separation chamber (40) from the first end (201) toward the second end (202) to at least the gas outlet (23).

19. The water and air separation apparatus according to claim 1 or 2, further comprising a settling portion (30) connected to the liquid outlet (22) of the guide portion (20) so that the white water discharged through the liquid outlet (22) enters the settling portion (30).

20. A paper machine comprising at least one water and air separation device (100) according to claim 1 or 2.

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