FI119292B - Method and apparatus for drying a paper web - Google Patents

Description

119292

METHOD AND APPARATUS FOR DRYING PAPER PAPER

The present invention is directed to a method and apparatus for drying a paper web or the like as defined in the preamble of the independent claims below.

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The invention thus typically relates to a method and apparatus for drying a paper web or the like in a drying section of a papermaking machine or the like, wherein the web is dried against the heated cylinder surfaces of the drying cylinders and by blow-drying through at least one over-blow unit.

The invention further relates to optimizing drying of a paper web in a drying section of a papermaking machine or the like comprising a drying section consisting of one or more drying cylinder groups and at least one blowing unit. However, the invention is intended to be applicable to other types of drying sections, if necessary.

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It is known in the prior art to use double-wire and / or single-wire in multi-cylinder dryers for paper machines. Tia. Over the past 15 years, there has been a growing trend to use single-wire exports where • · 1 2. There is only one dryer wire in the drying roller group of 25, * · jonka: in support of which the web passes through the entire group so that the drying wire presses the web with the drying cylinders * «against heated cylindrical surfaces and rolls or rollers between drying rollers . Thus, in single wire delivery, the drying cylinders are outside the wire loop and the swivel · 3: cylinders or rollers inside it. Existing • • · *. dehumidifying parts consisting solely of • · ♦ so-called. from standard single-wire export groups with dry • • * ·; · 35 ink pens in the top row and swivel cylinders or rollers in the bottom row.

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In order to heat the drying cylinders, steam is introduced into them and the temperature of the drying cylinders is controlled by adjusting the steam pressure and / or the steam flow rate. It is also possible, though infrequently implemented, to control the final moisture in the dryer section by adjusting the machine speed. In this case, the steam pressure is kept constant, most often with drying capacity limited machines at maximum pressure, whereby the final moisture can be increased or decreased by slowing or accelerating the passage of the web 10 through the drying section.

The most commonly used vapor pressure control systems are the so-called. cascade control and thermocompressor control, such as described in TAPPI NOTES, 15 Practical Aspects of Pressing and Drying, Short Course 1990.

One problem with these conventional-type dryer sections, in which the drying is performed entirely on the drying cylinders using either a single wire feeder or a double wire feeder, has to do with adjusting the drying power. Generally, the drying power of the drying cylinders is adjusted to achieve the desired final moisture in the web by controlling the pressure of the steam supplied to the cylinders. The adjustment is relatively slow, and thus the adjustment does not react optimally quickly to sudden changes in the moisture of the web, e.g. from the press section or the wire section. Specifically, vai. ···. don, run-in and run-off drying ···, the final adjustment is optimal by adjusting the steam pressure by φ φ 30 due to the large mass of drying cylinders. The controls have used, for example, a dry matter measurement based on IR measurement • φ * ··· 1 after the last drying cylinder ja φ. ··· and feedback to control the vapor pressures of the drying cylinders, conventionally kuivat φ φ.1. 35 main steam groups. This type of adjustment has worked without problems in the case of constant speed production and there have been no orbits. However, adjustment problems occur during paper type change, web break, or start up of the paper machine.

5 When changing paper grades, problems with conventional drying parts are caused by the fact that each drying cylinder has a high heat capacity due to its high mass, whereby the temperature of the drying cylinders changes slowly. As a result, the thermal state changes of the drying cylinders have not been rapid enough for species change. Sometimes the necessary changes in drying power adjustment have been made by changing the press section loads, but this also changes the paper quality characteristics, which of course is usually not the desired way. In addition, when the press portions are changed, the transverse profiles of the paper web also change, whereby, for example, the moisture profile often has errors. For the reasons stated above, when changing species, the roller may be used to reel the web with an incorrect final moisture or quality level. In prior art solutions, it takes about 15 to 20 minutes after a species changeover before a new equilibrium is reached. For example, with paper machine speeds of 1500 to 1800 meters per minute, a large amount of paper • · · y.m 25 is formed during this time, which means that a lot of poor quality paper has been produced. For a wide machine, the amount may be 10 to 20 tons.

• ♦ 4 • 4 4 4 4 · ;; * In the event of an outage, problems arise eg 4 · 30 that the drying roller Interit overheats when no paper web is applied to the drying section, which would remove the heat energy

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the cylinders. Cylinders that are too hot cause problems with the head • 44 after a break in the head; . ·, When the tin strip is caught in hot cylinders. In addition, too 4 4 · 35 hot cylinders dry the thread strap too much, 4 · making the strap brittle and losing its strength properties • 44 V: which can cause problems with the head strap. In addition, during the application of the threading tape after the web break, the 4,114 • 4 4 · 4 • 4 4 • · 4 • 4 4 • · 4 • 4 4 · · 4 • long before the drying cylinders are brought back to equilibrium 5. In the event of an outage, in the past, there has been virtually no other way to control the situation than to reduce the vapor pressure during the outage. This, in turn, has resulted in the final humidity not being at the desired values after the web break. In addition, it has taken a long time before the situation can be restored to normal driving conditions.

In the start-up phase of a papermaking machine, it is customary to first retrieve the control values established for the corresponding runs, e.g., in Tables ai-15, to determine the vapor pressures suitable for a particular paper grade and to control the vapor pressures of The vapor pressures to be selected and their temporal creep, or change, can also be based on the las-20 chemical models and the values derived from them. Conventionally, when the web is introduced into the machine, vapor pressures slightly below the optimum pressures are applied, and then the vapor pressures are raised to the desired level. Due to the high heat capacity due to the high mass of the drying cylinders 25. slow start-up, which takes time before we get to

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to the familiar situation. This is problematic because it generates a lot of wrong paper during startup.

30 * · • 1 "I The problems described above are therefore mainly due to the high heat capacity of the drying cylinders * · **** and their long response time to the required temperature changes.

* 35 The drying section is the most energy consuming part of the paper machine.

m. . ·. It can be said that even more than 2/3 of the paper machine energy consumption .1 ··. the litter will be partially dried. Therefore, the drying section must be used economically, that is, in order to achieve the highest evaporation efficiency and high quality drying results as well as low energy consumption. The drying must also be uniform across the 5 webs. Cylinder drying is the most common drying method used to date.

The profiling of the web, i.e., the control of evaporation to be uniform across the web, cannot be accomplished by adjusting the steam-10 pressure of the cylinders or the speed of the machine. At some points on the web, there are often lines in the drying section, or even before, in which the web dries more than at other points. Variations in the moisture profile of the web to be dried upon entry into the blowing unit are not only due to the uneven drying of the drying section itself, but are often due to the uneven dewatering of the press section. Fluctuations in the moisture profile may also be due to the uneven solids profile already present on the wire section. Changes in the need for drying also occur when species are changed. Such moisture profile defects must be corrected.

Previously, attempts have been made to correct moisture profile defects by spraying across the web from matched spray lines. or jets of water from the nozzles to these locations · * · .. so that the moisture level in the web is leveled. Of course, adding water to the web is less advantageous from the point of view of energy consumption, since the water sprayed due to the adjustment has to be evaporated again at a later stage • a Y, '. from the web. Another alternative way to correct the moisture • • '· ** feeling error has been to use infrared dryers fitted across the web, which evaporate the water, especially at the humidest points of the web. Infrared dryers are »» · 35 relatively large consumers of energy.

• · a a a. ···. In the case of cylinder drying, the web to be dried is passed over the surface of the dryer cylinder by pressing on the wire, whereby the opposite side of the web heats and dries more efficiently than the other side of the web. In today's high-speed machines, in which the web is dried using the y-5 civilian thread, only one side of the web is contacted with the drying cylinder surface in each drying group, and thus dries more efficiently than the other side of the web. The one-sided drying of the paper web is further emphasized if the paper web is always carried in the different drying cylinder-10 blade groups with the same side of the web in contact with the drying cylinders. The paper thus dried on one side tends to curl as a sheet, which causes great problems in the further processing of the paper.

15 In order to improve the above-mentioned problem of bias, i.e. curvature, it has been proposed that a so-called "sink" be fitted to the drying section. the inverted group through which the web is guided, supported by the wire, so that the other, less efficiently dried side, passes into contact with the drying cylinders. The solution then requires a different drying section structure, in which the drying cylinder and the wire loop, unlike other drying groups, are arranged to pass below the web. In this case, the paper wreckage generated during a web break or start-up drops down into pockets formed by a wire mesh fabric, between the drying cylinders and the wire, from which the wreck may be difficult to remove. Due to the deburring problems, the runnability of such an inverted drainage section is poor in the event of web breaks and start-ups. In contrast, in a conventional single wire thread 9 · 30, the wire loop is arranged to travel along the • · • · \ Y. above, so that the wreck • j '* ·· formed in the event of a web break will freely fall below the machine from where it can be easily removed.

It is therefore an object of the present invention to provide,. an improvement to the problems described above.

··· • ··:: ·· * ··· • · ♦ • · • ·:: ·· · 1 1 9292.

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It is a specific object of the invention to provide a method and a drying section in which the drying power can be adjusted quickly, for example in the case of paper type changing, web breaking and starting.

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A further object is to provide an energy-saving method and device that enables rapid total evaporation control, e.g.

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It is also an object to provide a method and a device which allow precise evaporation control, such as profiling, also in the transverse direction of the web.

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It is yet another object to provide a method and apparatus for minimizing the unilateral drying of the web and the resulting curvature.

It is a further object to provide a method and apparatus for adjusting the drying of the paper web which enables easy maintenance of the drying section, rapid removal of the wreckage and thus good runnability.

In order to achieve the above objects, the method and apparatus of the invention are known from what is stated in the characterizing part of the independent claims below.

• · • ·, ···. 30 The invention therefore relates to a conventional drying cylinder • • y. '.' instead of a drying dryer based on drying, where both over-drying and drying by drying cylinders are applied. For these types of dry parts, for example, the applicant's Finnish • • 1 * ...: 35 examination applications EN 971713 and EN 971714 are referred to.

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. ···. In this application, "blow drying" is intended to mean both blow drying directly on the web and blow drying through a wire or similar transport fabric. Also suitable for drying porous webs. flow-through drying is within the scope of blow-drying according to the invention. According to the invention, the blow-drying may be applied to a web passing over a large cylinder, roll, suction roll, flow-through cylinder or the like. The blow-drying may also be linearly applied, e.g., to a web supported by a wire or belt supported by rollers or blowing boxes. The linearly extending web may be arranged to run in a horizontal, vertical or oblique position. Preferably, the blowing medium is hot air or superheated steam for 15 minutes.

To achieve the foregoing and further objects, a typical method of drying the paper web or the like in a drying section having at least one blast-drying unit is essentially characterized in that the paper has a final moisture content and / or some other machine-specific quality. adjusting the power of the blow-drying 25.

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The apparatus according to the invention for drying a paper web or the like in a drying section having at least one blow drying unit has a main feature of comprising a measuring device pape. «1 YAt for measuring the final web and / or other machine direction quality and / or cross-sectional profile of the web and means for adjusting the blowing power of at least one blowing unit based on the measurement result.

»· 35. According to the invention, blow-drying may be carried out on the · · · .1 ··. uses a variety of transient phases such as: • 1 1 · · i 1 i • 1 1 t · ·:: 2 ♦ 1 1 9292.

9 to control changes in drying capacity during switching, web break, and start-up, to eliminate, or at least minimize, problems occurring during these steps.

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The advantages of the invention are based in particular on the fact that the overflow reacts very quickly to the control measures, whereby it is possible to take care of the rapid drying power adjustments required for, for example, change of species, web break and start. In addition to the quick adjustments of the drying power, the steam pressure of the drying cylinders is preferably also adjusted in the drying section.

For example, an optimization algorithm known per se can be used to control the drying power of the drying section and drying method of the invention, which optimizes the drying costs and / or paper quality characteristics. According to the invention, it is also possible to use, for example, MPC (Mo-20 del Predictive Control) control, i.e. response-based multivariate control.

When, according to the invention, the blowing is used to control the drying efficiency, the blowing 25 can optionally be controlled with one or more different blowing parameters: such as the blowing speed • · ·; ·. , the temperature of the blowing medium, the blowing medium I ·. ·. moisture and the distance of the blowing hood from the web (particularly advantageous during breaks). Blowing Hoods • · *,. 30 may also be constructed of machine direction blocks, whereby each block may be individually adjustable and / or lockable if necessary. To adjust the cross section, the overflow hoods can also be divided into transverse • · · sections in which the above overflow *, * '/ 35 parameters can be adjusted together or separately.

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When changing the type, it is generally known in advance that the required setting values for the paper type, e.g., the vapor pressures of the drying cylinders, are known in advance. to the desired end product. Thus, the vapor pressure can also be set directly at the start of the 5 species exchange or gradually desired when applying the method of the invention. However, since this adjustment is slow, according to the invention, the same blowing is controlled, either on the basis of an existing on-blowing model to calculate what adjustment action is required or by continuous feedback control. As the drying efficiency of the cylinders gradually changes, this change is compensated for by an opposite change in the blow drying efficiency.

15 In the paper machine start-up phase, the drying cylinders are first heated according to known heating sequences. The blowing hoods are preheated accordingly. The running parameters can then be set according to the preference values or drying simulation calculation. The Ta-20 rake coupling can then be used to control the drying cylinders and the blowing values so that the desired quality parameters are achieved.

When starting to drive a completely new type of paper, one of the 25 memories will be the first one to choose from: the set values of the paper type closest to the hips and then ♦ * · .. utilize these set points and apply feedback by applying blowing and preferably vapor pressures to obtain the desired values of the new paper type.

• · ··· ··· * · '·· * In the event of a line break, the vapor pressures of the drying cylinders are dropped, the overflow hoods are opened and the wreckage is guided away by the wreckage conveyors. The hood's own weather system ··· 35 takes care of the bypass inside the hood, roll,, *. adjusting the sun's feed and blowing speed, away tollman ···. * ··. and fresh air adjustments. When the track is turned on after the head stroke »119292, the operations are naturally reversed and the necessary drying power corrections are made by blowing.

Naturally, the invention is applicable not only to the specific steps described above, but also to the control of the drying power during normal running. According to the invention, the quality of the paper can be optimized all the time also in terms of quality and at the same time applying cost data. In this case, the position of the blowing unit in the dryer section according to the invention can also become a control parameter.

The blowing site is contemplated in a particular embodiment of the invention wherein the dry content of the paper web dried from the press portion of the paper machine and passed through at least one drying cylinder group, and preferably to more than 70%, even more than 75% controlled by passing a paper web, supported by a wire or the like, through a slot formed between 20 - one or more webs or linear overflow hoods and - one or more webs or curved or linear surfaces such as a cylinder, roller or vacuum box. ♦ *; - blowing said slit in said slot

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one or more blowing hoods: V. per square inch of a plurality of dry transverse • * * # ϊ 'webs. • pre-set successive hot air jets • · 1,. ^ 30. If desired, steam jets may be used instead of air jets, however, special requirements for the hood structure of the hot steam hood and for example sealing needs must be taken into account.

··· • · · · ··· · € 4ϊ 35 An overflow blanket is a box, blown over by hot air or steam jets, per se, perforated, with holes, slits, or other nozzles. » · ··· f ··· · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · ·

Preferably, a vacuum box means a box-like structure providing a low vacuum between about 100 to 400 Pa, preferably 200 to 300 Pa, between the vacuum box and the wire / web, the web side being substantially planar. This relatively low vacuum is intended to prevent the web from being detached from the wire. The vacuum is used to prevent, for example 10, the web from flapping and touching the overflow felt due to overhead blows. The purpose is to guide the web in a controlled manner through the gap formed between the boxes. The required low vacuum can advantageously be provided by a blow box, such as e.g.

15, or a suction box.

A typical papermaking dryer portion may be divided into three portions, 20 to a first portion where the paper web is substantially heated while still increasing the dry solids content of the web, typically between 40 and 60%, - a second portion where the bulk of the bulk water in the web is removed by uniform evaporation through which the web is passed through one or more IV strips and with a dry solids content of the web ···: ·. typically increases between 45% and 85%. - to the third section where the web is finally dried to dry • · e *. and where the dry solids content of the web typically increases between 75 and 98%.

In a particular embodiment of the invention, the blowing unit which provides the precise drying control can be fitted to the optimum range of drying control and energy consumption, e.g. in the area where the web has already reached> 70%, preferably 75%, of dry matter content. The said area is located at the end of the drying section, *; ·· * 13 119292 typically the last or second last drying cylinder in front of a group, in a dryer section with a single wire port of a typical drying cylinder group comprising about 3 to 8 drying cylinders.

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The relative drying power of the drying cylinders decreases when the web reaches more than 70%, typically more than 75%, of the solids content, i.e. after most of the easily evaporable water has left the web. However, by blowing over such dry web with good drying power, water that is more firmly bound to the web can be removed.

The solution 15 in accordance with a specific embodiment of the invention takes advantage of the novel finding that over-blowing, as an effective drying impulse, can advantageously influence the drying of the web, not only during the initial drying stage, i.e. increasing the temperature of the web. The use of drying cylinders is most energy efficient in the middle stages of the drying section.

capable of affecting web profiling with a dry solids content of more than 70%, even more than 90%, up to 25 dry solids. The paper web profiling has been attempted by prior art methods »» · $ ·. at the end of the drying section.

- advantageously, in the final drying section of the drying section, when the dry solids content of the web is already more than 70%, typically more than 75%, it is possible to remove the paper curl in the region after which the paper web does not • · * ··· * is no longer as susceptible to drying on one side as the center of the drying section. In the past, the use of inverted groups at the end of the drying section has been proposed for controlling curvature.

I'll "·. Now it has been found that the optimum range for combined drainage- S * ft *

Ml • · f • · ·

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:: • 14149292 for lifting, profiling and curvature control by blowing located in the remainder of the dryer with a dry solids content of more than 70%, preferably above 75%, up to about 95% solids up to 5, most preferably between 75% and 85% . A very short drying impulse of less than 1 second, even less than 0.5 seconds is often sufficient to control the drying. A short effective drying impulse can be achieved by a linear overflow of from 1 to 20 m, preferably from 5 to 10 m.

In general, it may be advantageous to carry out the final drying after over-washing with drying cylinders, one or two groups of drying cylinders. In some special cases, the blowing unit of the invention may be fitted to the very end of the drying section. This is especially useful when the final dry solids of the web to be dried remain 90% or only slightly over it.

20

Regardless of the reason for the change in drying need, the drying power adjustment is generally based on the dry matter content measured after the drying section of the web. Of course, the measurement can also be made elsewhere, before or after 25 blowing units. Measured dry matter content ·; The drying power of the blowing unit according to the invention is also controlled. The drying power of the typical air blower unit of the present invention is controlled by adjusting the temperature, humidity or speed of the air blowers.

Preferably, the blowing unit uses blowing air derived from a paper machine room, with a hood ·] * ': 35 in the enclosed drying section, the hood recirculation air or the recirculating air of the blower. The air temperature of the blowing air is raised and / or its humidity level is lowered before blowing X 11 "9299292 per paper web. The recirculated air of the different blowing units can be heated with a common gas, eg in a separate space adjacent to the drying section! With oil burner or other similar heater.

On the other hand, a separate burner or the like can be integrated into each of the blowing unit or part of the unit, in the direction of the web or in the cross direction of the web, whereby the different blowing units or parts thereof can be independently adjusted.

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Preferably, the air blown hood or unit according to the invention is blown with hot air, the temperature of which is set between 40 ° C and 500 ° C, preferably between 200 ° C and 400 ° C, depending on the drying power required.

The air jets typically have a moisture content ranging from 0 to 300 g H 2 O / kg dry air.

On the other hand, the drying power of the blowing unit can also be controlled by adjusting the speed of the air jets. Here, the velocities of the air jets 20 are typically maintained between 40 and 200 m / s, preferably between 50 and 150 m / s, most preferably between 70 and 120 m / s.

The effective blow-off of the moon or steam jet according to the invention is extremely fast, *. virtually immediately, without delay, to regulate drying on the papermaking web. impingement

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\ * t.t. the change in adjustment is shown in full paper · * *. after a few seconds.

: '30 f ·· «* * ·· ** The temperature of the hot air can simply be adjusted by adjusting the burner fuel valve. It does not take time to raise or lower the temperature of the appliance itself, such as when drying with a drying cylinder. Drying power of 1: 35 can be changed very quickly between 20 and 100% by the blowing according to the invention. Full- «t ·; **. the change is typically accomplished in less than 30 seconds: ··· 16 in 119292 seconds, usually less than 10 seconds, which is only a fraction of the time required to effect a change by conventional cylinder drying. Adjustment by cylinder drying takes several minutes.

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In the drying section, the optimum adjustment ranges for the overflow can be successively fitted with two overflow units, whereby their drying power can be adjusted either individually or together to achieve the optimum drying result 10. In general, it would be advantageous to fit the successive blowing hoods into the drying section so that the drying power of the air jets from the first blowing hood is on average higher than the drying power of the subsequent jets from the subsequent blowing hood.

Each blowing unit according to the invention preferably comprises a plurality of adjacent rows of nozzles formed by successive blowing nozzles arranged across the web. These nozzles can be arranged to be adjusted all with the same adjustment, each nozzle individually or a specific group of nozzles separately. It is often advantageous to divide the blowing unit according to the invention in a plurality of blocks in the transverse direction of the web, whereby the nozzles of different block sizes can be individually adjusted. Loh-t. * »Can be as narrow as 100 mm. Typically, the width of the blocks is between 500mm and 2000mm.

· «· • * · • · * *. The invention will now be described in more detail below. 30, the details of which, however, are not to be construed as being limited in any way, and in which:

Figures la / lb show schematically and exemplarily a drying section of a papermaking machine in which · '**: 35 uses the method of adjusting the dry # * .4 ink and blowing according to the invention. ·· .M _:: • e · ··· • no • · · 1 m · * · ··· 17 119292

Fig. 2 is a table showing, by way of example, the effect of the blowing blast temperature and blowing rate on the drying capacity; Figures 3a-3d schematically show previously known blowing units fitted in connection with drying cylinders or suction rolls; Fig. 4 is a diagrammatic cross-sectional view of a linear 10 blowing unit applying the invention fitted between two sets of drying cylinders,

Figure 4a schematically shows an enlargement of the vacuum box of Figure 4.

Figure 5a schematically shows a portion of the nozzle surface of the overcoat of Figure 4,

Figure 5b schematically shows, in vertical section, a portion of the overflow hood of Figure 4,

Fig. 6 shows another linear blowing unit according to the invention, similar to Fig. 4, Fig. 7 shows a third linear blowing unit according to the invention, Fig. 8 shows a typical And then profiling with a device according to the invention.

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In Figure 1a, the invention is illustrated in a front drying section, i.e. * · ·. · **. 30 immediately after the press section, with respect to the fitted drying section. However, this is in no way intended to limit the invention to the front drying section only.

• · IV. The invention is also fully applicable to the intermediate or post-drying section. The term "drying section" as used in the specification and claims herein refers to both the entire drying section and its portion, such as e.g. after-dryer section.

♦ ♦ • · · • »» · · · · 18 119292

Figure 1a illustrates a particularly preferred drying section solution in which the invention is applied. In Figure 1a, the paper web W is brought from the press section (not shown) of the papermaking machine to the beginning of the drying section 5 by its press fabric to its first drying unit Rt. In the case of Fig. 1a, the first drying unit is a flat drying unit, i.e. a linear overflow unit Mo, with an overcoat hood 10 from which hot air and / or steam is blown onto the web 12 passing through the wire 12 with the horizontal running of the wire 12. 14 supported. Said means for supporting the horizontal flow of the wire 12 and thus also for the web consist of e.g. grooved rolls and / or suction or blow boxes. With the blowing module Mq of the drying unit R 1, an intensive drying energy impulse is applied to the web W from the blowing hood.

In the blowing module Mo, the paper web, supported by the upper course of the dryer fabric 12, runs linearly in the horizontal plane so that it does not exhibit major directional changes and thus is not subjected to high dynamic forces that could cause a web break that is still relatively moist and thus weak. Inside the blowing mouth 10 there is an orifice arrangement for providing blowing that blows hot drying gases such as air • ·: * "or steam into the upper surface of the web. In the drying unit Rj, in addition, or alternatively use weather- * "*! rolling equipment such as infrared heaters. The blowing unit and / or radiation devices of the drying unit Rj may be arranged in a transverse direction of the power of the web to provide a transverse profiling of the web W. for what. Although Figure 1a shows a horizontal mill. ···, an overflow module Mo, it is understood that other units, such as an overhead dryer apparatus based on a suction roll, may alternatively or additionally be used instead. At this point, the overflow module Mq may even be replaced by a set of cylinders, provided that the drying section can be utilized in a subsequent step in overcoat drying in accordance with the invention. In the flat drying unit Mq, instead of the conventional wire 12, an impermeable belt can be used.

Fig. 1a shows the first so-called "after" flat drying unit Mq. a normal (not inverted) drying unit R2 formed of a single-wire 16 drying cylinder group.

The wire 16, like most other wires, is only partially shown in the figure. The second drying unit R2 as well as the following similar so-called drying units. the normal downwardly open drying units R4, Re, Rg, Rj and R10 formed from a single-wire cylinder group comprise three or four to 15 rows of steam-heated contact drying cylinders 20 and a bottom row pivoting suction roll 22, e.g., VAC roll. The paper web W to be dried comes into direct contact with the surfaces of the steam heated drying cylinders 20. The rotary suction rolls 22 rai-20 na W remain on the outer side 16 of the drying wire.

In the drying section of Fig. 1a, following the drying unit R2, there is an overflow drying unit R3 comprising two con. a tactical drying cylinder 24, 24 'and an overflow module]; * · * 25 Mlf, which in turn comprises a large diameter Dt hole • · "jacketed overflow / flow-through cylinder 26, later referred to as the isocylinder, and its isocylinder: *** The diaper 26 partially covers the opening hoods 28, 28 '.

• · ·

A drying fabric 30 is arranged to pass around the contact drying cylinders 24, 24 'and the major cylinder 26 30 in the basement space below the floor plane Kt of the paper machine room. KT on the floor level of this space. Preferably, the central axes of the contact blasting cylinders 24, 24 'of the blow-dry dryer *, ·, R3 and similar follow-up blades Rs and R7 of the present invention are substantially substantially at the floor level Kj of the paper machine. • or about 20 119292, preferably slightly above.

The paper web W to be dried is introduced from the drying unit R2 formed by the first drying cylinder group, preferably in a sealed export, to the first contact drying cylinder 24 of the next blow drying unit R3, followed by the wire W 10, and henceforth to another contact drying cylinder 24 'of this unit R3. From this second cylinder 24 ', the web W is again preferably transferred as a closed export to the next so-called. to a conventional drying unit R4 formed of a drying cylinder group, which is substantially similar to the drying unit R2 described above. This is followed by another blow-drying unit R3 equipped with an isosyl cylinder, similar to the above-described blow-drying unit R3, and whose isosyl cylinder 26 is also located in the basement space 20 KT. After the drying unit R3, the web W is preferably further exported as a closed export to the next drying unit R6 formed of a drying cylinder group, which is similar to the drying units R2 and R4. Following the drying unit R6 is followed by the third isos cylinder • * · 25 blow-drying unit R7, the isos cylinder 26 is also · · in the basement spaces KT. After the blow-drying unit »· · • · [R7 is followed by three consecutive so-called" drying "steps. a drying unit Rg, R9 · · · and R10 formed of normal drying roller groups, each having three or four drying cylinders 30 · 20. From the last drying unit R10, the web Wout is led out of the drying section to a reel or after-treatment. i * ': to ly (not shown).

• · · • · • * *. Both so-called. the normal drying units R2, R4, R6, Rg, R9 and R10 • · · 35 and the over-drying drying units R3, R3 and R7 are • · * ·; · * open downwards so that the paper wreck is easily: T: removable by the · · ♦ · · · · · 21 to the pulper with 119292 jet or below. Underneath the overlay hall modules Mo, Mu Mj and M3 there is great space in the basement spaces KT or below for various devices such as ducts through which heating media such as heated air or steam are introduced into, for example, modules 28, 28 '. On top of the drying units R2 - Rjo is an air-conditioned dryer section hood 32 known per se.

In the following, the adjustment method according to the invention will be described with reference to Figures 1a and Ib. Figure Ib shows the control circuits of Figure 1a in simplified form. Fig. Ib omits the first drying unit Rj of the drying section, i.e. the flat blowing module Mq, but can be used, as well as the overflow modules Mj, Mj, M3, to rapidly adjust the drying power required by the drying section as described below. In Fig. Ib, the same reference numerals as in Fig. 1a are used for corresponding parts.

After the last drying unit Rt0 of the drying section, a measuring device 34 is provided for measuring the moisture of the paper web W. Of course, the adjustment may, if desired, be based on other measurements of the paper web quality parameters, such as web brightness, or paper web W.

• · '·' ·· 1 25 for cross-sectional measurements. From the measuring device 34, the results of the measurement: '· 1 are fed through the control unit 36 to the steam pressure control 38 of the blades 20, 24, 24' and to the overhead control unit 40 to control the drying of the paper web W - · 1'1 · 30 infiltration units Mq, Mj, M3 perform the fast action required for drying, for example ···. Therefore, in the event of a web break, a change of species and a start-up phase, • the steam pressure control unit 38 T takes care of controlling the steam pressures of the drying cylinders 20, 24, 24 'to a desired level.

··· ♦ ♦ • ♦ »· 1 yr ···. The blowing control unit 40 can control the blowing parameters Mo, M ,, Mj, M3 of the blowing modules Mo, M, Mj, M3 according to the invention, such as blowing air / steam temperature, velocity or humidity or the distance of the hood from the web, either in one module Mo, Mj. , Mj, M3 at a time in 5 or more modules simultaneously. In the case illustrated in Figures la and ib, there is an Mq of the blowing modules,

Mj, Mj, M3 for transmitting control parameters, each with its own control units 400, 40j, 402, 403. If necessary, quick drying power control measures are controlled by one or more plurality of blowing modules Mq, Mj, Mj, M3 such that paper moisture and other properties are quickly desired. In the blowing modules Mo, M 1, M 1, M 3, one or more of the following control variables can be controlled at the same time: pu control speed, blowing air temperature, blowing air humidity and / or blowing hood distance w, to achieve desired control operations. On the other hand, a blowing hood or block thereof can be completely switched off if desired.

In turn, the vapor pressure control 38 of the drying cylinders can control the vapor pressures of conventional drying cylinders 20 or contact drying cylinders 24, 24 'of each drying unit R2, R3, R4, R5, R6, R7, R8, R9. by controlling the vapor pressures of one or more drying cylinders or contacting cylinders individually or by controlling the vapor pressures of one or more groups of cylinders by means of actuators 382, 382 ', 382' '; , 383, 384, 38s, 386, 387, 388, 389, 3810, 3810 1, 3810 '', based on transmitted signals. The control of the vapor pressures of several drying groups 30 is also within the scope of the invention, since often, for cost reasons, there are steam groups. less than wire groups.

· «« «· ·« »*

During normal running, drying and / or other quality parameters can be kept within the desired limits by, for example, adjusting 1 * · only one or two air blowing modules Mq, m ,, Mj, M3. One or more of the blowing parameters of these modules, or the distance W of the blowing fan W from the web W 119292 is controlled based on the measurement results provided by the final test measurement 34 to obtain the desired final moisture or quality characteristics. If necessary, the final moisture or 5 other quality parameters can also be corrected by adjusting the vapor pressure of one or more cylinders 20, 24, 24 'or a group of cylinders of the drying cylinder units R2 ... R10 via a vapor pressure control 38.

The blowing parameters are controlled by the blowing control units 40, 400 / 40j, 402, 403, either based on an optimization algorithm or utilizing multivariate control. If necessary, both the blowdown and the vapor pressures of the drying cylinders can be controlled simultaneously to achieve the desired quality parameters.

When a species change to control system 36 is performed, the desired paper type information is retrieved from memory 42, e.g., a table, and based on this species information, control unit 38 controls the vapor pressures of the desired drying cylinder groups R2 ... R10 20 that the vapor pressure is gradually adjusted to the desired level. At the same time, a quick adjustment is required to change the species to obtain the desired quality properties as soon as possible, through the blower control 40, either by ♦ · · • controlling the blower based on the target value of *: ** the required blowing parameters or by continuous feedback control from the measuring point 34.

• * 4. · **. 30 • 9 · * · In the start-up phase, heating of the drying cylinder, ···, en 20, 24, 24 'is initially performed according to known heating sequence parameters, while simultaneously performing a blow-up operation of Mul, Mlf M2, M3 hoods. Then, the running parameters are set according to the preset values and the feedback function controls the blowing to achieve the desired quality quickly, then the blowing is further adjusted by the cylinders. as vapor pressures change until they have reached their target values.

During the line break, the necessary adjustments are made, i.e. the vapor pressures of the drying cylinders 20, 24, 24 'are controlled to the breaking vapor values used during the break, and at the same time the cover control modules Mq, Mj, Mj, M3 are opened. Internal control systems 10,400 ... 403 provide bypassing inside the hood, lowering the gas supply and lowering the blowing speed and closing the exhaust air and opening the fresh air. After the break, the above operations are performed in the reverse order and the quick quality correction 15 is performed by adjusting the blowing parameters until the drying cylinders 20, 24, 24 'reach the desired target values.

When driving a new paper grade, the parameters 42 of the memory 42 closest to the memory 42, e.g., from the table therein, are selected, and the blowing modules Mq, Mi, Mj, Mj and the vapor pressures of the drying cylinders 20, 24, 24 'are selected. The feedback control then adjusts the quality parameters • · '*! · * 25 to obtain paper with the desired properties.

It is also advantageous to adjust the paper or board web moisture, *, ', tension or other quality profiles in different driving situations, according to the invention. At least fast · ***: 30 cross-sectional corrections should be made * · ♦, set can then, in the longer term, possibly be implemented by other profiling devices if it e.g.

* "in terms of cost is thus cheaper.

Table 1 shows the effect of the blowing temperature and blowing rate of the blowing module Mt, Mj, M3 on drying.

Ml • «• ·

»M

25 to 119292 capacity. The table is based on the results obtained with the measurement results verified by the drying section simulation program in the case where one or two overflow-5 modules M 1, M 1, M 1 of Figure 1a are adjustable. In the table, the inflator modules are denoted by reference marks PP1 and PP2. The simulation program assumed a paper machine speed of 2000 m / min and a paper web width of 9.5 m and a paper web weight of 41.4 g / m2. The first part of the table shows, as indicated above the table, the effect of the blowing air temperature control on the drying, with an overflow speed of 90 m / s. Correspondingly, the second part of the table shows the effect of adjusting the blowing speed on drying with a blowing air temperature of 350 ° C. For example, it can be seen from Table 15 that a single blowing unit can perform a humidity correction of about 2 percentage points at a blowing rate of 90 m / s by varying the blowing air temperature between 250 ° C and 350 ° C. Similarly, increasing the blowing speed from 60 m / s to 120 m / s results in a change of about 2.5 percentage points in one and a change of 5 percentage points in two blowing units.

Thus, when the invention is applied, the drying power can be increased by adjusting the overhead and blowing profile of the cylinders in the drying section, by: • * I '· * air or hot / superheated steam blowing units, *: **: rolls or flat wire runs. The following: *** · Figures 3a - 3d show some of Figure 1a ··. ***. 30 of the more recommended blower modules for the application of the invention »·· M! - M3 abnormal ···, inflatable modules.

Fig. 3a shows an overflow concept where, in the inverted drying section, the suction suction of the drying cylinder 20 upstream of the drying cylinder 20 is provided with a curved suction section of the Elan 22. surface inflatable hood H. Inflatable air hoods 115292 26 hot air jets of the hood, not shown further, are directed to the side of the paper web that is contacting the surface of the hot cylinder by the drying cylinder. In the case shown in Fig. 3a, it is fitted outside the wire loop so that it is easy to maintain.The paper shred formed during breaks or machine shutdown drops into a pocket P formed by the drying wire at the drying cylinder, which may be difficult to remove before restarting the machine.

Figure 3b shows a slightly different blasting solution in which the blowing hood H is mounted on the blades 20 of the drying section 15 of the dryer section with a single wire vent to blow hot air through the wire F towards the web W. In the event of a web break. However, maintenance of the Hood H can be difficult to arrange. The over-blow 20 provided in connection with the conventional drying cylinder takes place through the wire towards the side away from the drying cylinder. Thus, in addition to increasing the overall drying power, the one-sided drying of the web can also be smoothed.

Fig. 3c shows a portion of a drying section m · • 1 2 3 ·· with a double wire spout having drying cylinders 20 'and!'. J 20 '' in two rows. The inflating hood H is fitted

·; ··: to blow hot air through the wire F towards the web W

: "1 · As shown in Figure 3b. When a web break occurs, · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · in addition to the upper blow-out hood H '* "in the upper blow-out hood H' *" in connection with the lower drying cylinder 20 ''. In the event of an orbit! # S # S 35, in this case too, the wreck builds up in pocket P of the lower! 1 ”: wire F ''.

··· · · 2 • «· e 3 • ψ • · 27 119292

In the case of Figures 3b-3d, hot air is blown through the wire F, F 'towards the side away from the drying cylinder 20, 20', 20 '' of the web W, which reduces the bias and drying of the paper. However, wire F, F '5 both interferes with the air blast and weakens the drying power of the hot air blast. In the case of energy consumption, it should be noted that the blast through the wire towards the web increases the energy consumption as compared to the direct blast to the web. In addition, the fabric made of synthetic-10 material limits the temperature of the hot air. Generally, air blowing at about 300 ° C cannot be blown. In addition, in the cases of Figures 3b-3d, the blowing hoods are inserted inside the mesh loops, which makes it difficult to access the hood 15 and thus also to maintain the hoods.

In the overflow modules Mt-M3 shown in Figures 1a and Ib, the above disadvantages do not occur.

Fig. 4 shows an inflating unit 428 according to a specific embodiment of the invention, fitted between the drying cylinder groups 430 and 432 having a single wire outlet. The blowing unit comprises a linear blowing hood 434 which, together with two linear vacuum hoods mounted on the underside of the hood 25, forms a linear slit space «· · | The paper web 418 is arranged to pass through a slit ·: * ·: space supported by a drying wire 440.

··· • · • · * ··. ** ·. In this solution, the paper web is preferably adapted to * · * pass over the blast unit by the support of the vacuum created by the wire and the vacuum box. Vacuum • · I "holds the web in the wire. Hot air blowing could« · "remove the wire from the wire without the aid of vacuum. In this solution, a vacuum box is preferably used to provide a vacuum which, by blowing, produces a ··· vacuum that holds the web in the wire. If desired, other types of suction box may be used to provide vacuum for the M * 28 119292.

The wire 440 supporting the paper web passes through rollers 442, e.g.

The wire and web thus support, supported by the rolls 442 and the vacuum boxes 436, 436 ', at a suitable distance from the vacuum box opening 44 and the opening of the blowing lip 10 the stud is typically about 10 to 50 mm, preferably 15 to 25 mm.

below 15 The web 418 carrying the dryer fabric is shown in Figure 4 the case kuivatusviirasilmukan arranged inside an under-pressure box according to the two of Figure 4a 436. The vacuum box out of the arrows A as shown blowings arrow b direction of the air 20 of vacuum box 436 and the wire 440 from the space between, thereby forming a vacuum in this space. Typically, a vacuum of about 100 to 400 Pa, preferably 200 to 300 Pa, is formed between the wire and the lid of the box.

This vacuum is sufficient to hold the web 418 stable over the wire 440. At the same time, the blows, arrows a, keep the wire · · * * ·· at a specified distance from the boxes 436 thus es-] *,! with the wire touching the superstructure of the boxes *: * ·; 445. The suction rolls 442 or the like control the passage of the wire 440 past the blowing unit. Below the vacuum boxes ···. ···. 30, the passage of the wire loop is controlled by conventional pivoting rollers 450.

··· • · · · I "The blow blade 434 is formed by a housing-like structure with a substantially 5 ^ 5 * 5 35 planar nozzle surface 446, i.e., limited to the paper web, formed on the side, nozzles, such as ♦ · «holes or slots for blowing hot air or SS vapor jets toward the web. A portion of the nozzle surface of one of the blow mats according to the invention is shown in Figures 5a and 5b. and 5b, the holes 535, are preferably disposed in a plurality of consecutive nozzle surfaces 546 in a plurality of adjacent rows of adjacent webs.The open area formed by the holes 535 or slots of the nozzle surface 546 is preferably 0.5 to 5%, preferably 1 to 2.5%. 10-100mm (15 -35mm).

10

The nozzles 535, as indicated by arrows a in Figure 5b, blow hot air or steam, preferably at approximately right angles to the web 518 on the side of the web that has not been in contact with the hot surface of the drying cylinders in the original dryer section 430 (Figure 4). Thus, the blowing unit forms a curvilinear portion in the drying section.

In the solution shown in Fig. 4, the hot air jets of the blowing hood 20 use the hood's own circulating air. The air returned from the web is led from the hood 434, through the tubes 537 shown in Figures 5a and 5b, to the hopper collecting space 539. From the collecting space, the return air 454 is led to one 452 through the fan 454 of Figure 4 and back to the blower hood. 434 to be blown heated again towards the web.

: * ·]: Some of the moist recirculated air is removed by fan 458 ···· through heat exchanger 460 to keep the humidity in the recirculated air suitable. New dry blowing air can be supplied to the recirculated air by fans 462, 464 through heat exchanger 460 and burner 456,

In the solution of Fig. 4, the paper web is conducted as a closed export from a dry roll 354 in a single-wire export competent to a wire 440 for passing over the blowing lip 434. Hot air is blown from the hood ··· toward the web to provide the desired effective drying impulse to provide 119292, adjust the drying, remove curvature and / or provide good profiling. The drying power of the air blown towards the web can be adjusted by controlling the temperature, humidity or speed of the hot air jets blown towards the web. The control of the hot air temperature is simply achieved by, for example, adjusting the burner 456. Similarly, the humidity of the hot air can easily be controlled by venting a greater or lesser portion of the moist recirculated air through the fan 458. The speed of the hot 10 air can be adjusted by adjusting the fan 454. In the solution according to the invention, the temperature of the hot air jets on the paper web is adjustable in several steps, whereby the drying power of the hot air jets can also be instantly adjusted higher or lower. Thus, the solution of the invention is capable of adjusting the drying of the paper web, e.g. after a change of species or after a sudden change in the press section, in a very short time, typically less than 30 seconds, even less than 10 seconds.

20

In the event of a web break, the paper shred in the blowing unit, the wreck, is easily removed from the linear portion between the blowing unit and the drying, rolling cylinder assembly 432 down to the floor level, where it can be quickly removed. Also, the • · ^ "overflow unit according to the invention, which is not surrounded by any wire mesh, * a bag in which a piece of paper could accumulate in the pocket during a web T * break, improves the machine's runnability. - 30 wires on 440 for maintenance.

. ** ·. The blowing unit according to the invention can be made to · · · · **. very short, one short blow-out hood and one vacuum box for the purpose of, for example, only removing the curvature of the paper web or improving the profiling. Even a short in- «. • S * is sufficient for profiling. tensile drying pulse, precision treatment, in the right position ·· »• · • ♦ • f» 31 119292 webs.

On the other hand, the actual blow drying can also be added to the blowing hood, whereby the blowing unit may be made longer if necessary. Figure 6 shows a longer inflatable unit formed by three inflating blades 634, 634 ', 634' '. A separate underpressure box 636, 636 ', 636' · is arranged below each inflating hood. As such, linear straight blowing hoods and vacuum boxes 10 are successively arranged to form a curved slot between them, such that the first blowing hood 634 and the vacuum hood 636 form an upwardly directed slit 638, a second hood / box pair 634 and a pair of slats 634 the third pair of hoods / boxes 634 '' and 636 '' form a downward slot 638 ''. The slit forms an angle <45 ° with the horizontal. The angles between the slits 638, 638 ', 638' 'are preferably 5-15 °.

20

Figure 6 further illustrates the entire hood 634 obliquely from above. The hood is marked with its division across the web into discrete parts or blocks 634a, 634b, and 634c. In the solution according to the invention, it is possible to * 4 [··· * 25 adjust the drying power of these various blocks, whereby, for example, · hot air can be blown at a lower evaporation rate I. · from the outermost blocks 634a and 634c and la evaporation from the middle block 634b. Often i ί the web dries more at its edges than at its center.

• 4 · ♦ ·· _ _:: 30 • 44

Fig. 7 shows the blower unit 728 of Fig. 4, which differs from the previous one, however, in that the blowing air is not using recirculated air, but rather the air drawn directly under the drier 766 of the dryer section. air is not collected from the web area, but the humid • 44 • t>. · air is allowed to flow freely into the t ··· space under the hood.

• · · 4 4 »· ft 4 • 4 444 32 119292

Fig. 8 shows a typical curve of the drying power variation of the drying cylinders in a conventional 68-cylinder single-wire dryer section. At the beginning of the drying section, step l is a so-called.

5 is a region of increasing evaporation, in the central portion of the dryer section, step 2 is a region of uniform evaporation, and in the remainder of the dryer section, step 3 is a region of descending evaporation.

The upper part of Fig. 8 also shows, by way of example, the optimum range of a drying section - the overflow optimum, i.e. the areas in the drying section where the web can advantageously be influenced by the cylinder blast 15 - the optimum area of the drying section where the profiling of the web , - the optimal curvature control range, i.e. the area where the curvature due to one-sided drying of the web can be most advantageously reduced, - the optimum curvature control area with the drying impulse, e.g., a short over blast drying, and - the optimum range for combined drying; · * »Ί · * 25 for profiling and curve control.

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• • V

** '· 30 web has already dried to> 70% but not yet 95% dry content, preferably in the area where the web is. dried to a dry matter content of 75% but not more than · · 85% dry matter. Often, the optimum range for the blowing T will lie within the range of about 75% to about 35% to about 80% dry solids. This optimum range lies within s "*! In the dry ···. Drying section with nearly 70 drying cylinders shown in Fig. 5, with approximately 70 drying cylinders between about 48 and 61 drying cylinders .

Figure 9 shows, by way of example, profiling of a printing paper web with the solution of the invention. The upper curve of Fig. 5 shows the moisture profile of the paper web from the drying section, which in addition to the drying cylinders has a 5 m long blowing unit without separate profiling. The average humidity of the paper web is 5.3%, the peripheral areas 4.1% and the middle region 6.5% when the top-10 blowing air temperature is about 300 ° C and the speed is uniformly 80 m / s over the entire web.

The paper web is profiled by closing the outermost sections of the blower unit and increasing the blowing speed of the middle 15 sections to ISO m / s. In this case, the average humidity level remains almost constant at 5.1%, the edges humidity level increases and the middle part humidity level decreases. Humidity values range from 4.7 to 5.4. Thus, the moisture profile of the web is clearly leveled as shown in the lower curve of Figure 6.

The purpose of the linear overhead blowing unit according to a specific embodiment of the invention is not necessarily primarily to conventionally remove moisture from the web. Because the evaporation power of * · '· ϊ · * 25 superblower dryers can be changed very quickly, the drying efficiency of the dryer section can be adjusted more quickly than conventional * ·' * cylinder drying, even though the dryers of the invention are even just one song.

; · **. 30 This can be advantageously used for breeding, which is often the case with traditional hardware solutions. long periods when the solids content "creeps in" •. ···. before it reaches steady state. A fast-acting blowing unit can decisively suppress and even completely eliminate these phenomena.

• m · • · ·. *: ·. A great advantage of the solution according to the invention can also be seen in the fact that, due to the quick adjustment, the machine is lowered up and up. The design of the blowing unit is also likely to increase the runnability of the machine when, for example, wreck removal in the area of the unit is easy.

The blowing unit is suitable for use in controlling curvature of the web when the drying energy is introduced through a surface of the web that has not been in contact with the previous drying cylinders. In contrast to the solutions of Figures 2-4, the linear overlay-10 holding unit may also be arranged such that the slit extending through the web is vertical if this is desired for space use or for other reasons.

The relatively small size of the blowing units can be easily fitted to an existing drying section to improve the operation, humidity control, curvature and profiling of the drying section. The blowing units are easily divisible into discrete blocks which allow the unit to be used to adjust the transverse humidity profile of the web.

The invention has been described above with reference only to some preferred embodiments thereof, however, the invention is not intended to be limited in any way to the private home. Many modifications and variations are • · *: *. · Possible within the inventive concept * · * as defined in the following claims.

· * * * «« • ♦ «« »» »» »» »» »» »» » * • · * • · * • · · · • Φ m «· ·

Claims (32)

A method of drying a paper web, in which the paper web (W) method is dried against the at least one drying cylinder (20, 24, 24 '; 410) dryer cylinder surfaces (20, 24, 24'; 410) and then by blow drying by at least one blast , Mi, M2, M3; 434, 634, 734), characterized in that in the process the final moisture of the paper web (W) is fed, and that based on the measurement results, the effect of the blow drying is controlled by controlling the blowing speed and / or the blowing medium temperature and / or the humidity of the blowing medium. A method according to claim 1, characterized in that in the process the final moisture and / or quality property of the paper web (W) is controlled by controlling the meadow pressure of one or more dryer groups (R2 ... Rio) drying cylinder / drying cylinders (20, 24, 24). '). 20 Method according to Claim 1 or 2, characterized in that in the process the final moisture of the paper web (W) is measured after the last drying cylinder group (Rio) ··: 1 ·· of the drying section with a measuring apparatus (34). A method according to any one of claims 1-3, 3; characterized in that, in the process, paper • • · .2 · is regulated. The characteristics of the web (W) on the entire width of the web (W) on the basis of the measurement results of the measuring device (34) via ether coupling. 5. A method according to any of claims 1-4, characterized in that the effect of the blowing and / or the drying pressure of the drying cylinders is regulated on the basis of a method. 6. A method according to any of claims 1-4, characterized in that the effect of the blowing and / or the drying pressure of the drying cylinders is regulated in the method. 7. Process according to any of claims 1-6, characterized in that the method of controlling the blowing is controlled by controlling the machine-directed blocks separately and / or by closing the blowing blow. - the machine-oriented blocks 10 Method according to any of claims 1-7, characterized in that in the process, while the paper web (W) is changed, the drying effect is controlled by means of sort information or models describing kind change, which are taken to the control system (36) from a memory (42), that the control system (36) controls the pressure pressure of one or more dryer cylinder groups (R2-Rio) drying cylinders / drying cylinders (20, 24, 24 ') on the basis of the variety information by means of a control unit (38) and on the same thread is controlled by means of the control system (36) one or more inflating modules (M0, M1 (M2, M3) by means of a control unit (40) on the basis of the set value and / or with continuous feedback control from the measuring device (34)). Method according to any one of claims 1-7, characterized in that during the start of the paper machine, the drying cylinders (20, · ·) are first preheated in the process. ··. 24, 24 ') and the blowing hoods (10, 28, 28') and that the running parameters are controlled by controlling the blowing and, by regulating the pressure of the drying cylinders on the basis of the ä * feedback from the measuring apparatus (34) and the blowing effect is controlled by the drying effect of the drying cylinders: * : changes. * ·· • t · • * • «• · · *. 10. A method according to any one of claims 1-7, characterized in that during a web failure the coupling pressure of the drying cylinders (20, 24, 24 ') is coupled and the effects of the blowing modules (M0, Mi, M2, M3) to the values and, after the breaking, the pressure of the drying cylinders (20, 24, 24 ') and the effects of the blowing modules (M0, Mi, M2, M3) are coupled to the normal run values (W ) quality correction is performed by controlling the inflating parameters. The method of claim 1, wherein the paper web has been treated as follows in the dryer section of the paper machine (a) the paper web coming from the press section has been passed through at least one dryer cylinder group, (b) the paper web has been dried in said at least one dryer cylinder group on average> 70%, advantageously> 75%, and (c) the paper web has been guided from said at least one dryer cylinder group to a device which controls the drying of the paper web, characterized in that the dry web content is controlled by guiding the paper web advantageously or corresponding to 20 - through a gap-shaped space formed between one or more curved or linear inflatable hoods extending over the web and • · · * · ί · * - one or more curved or linear surfaces, such as a • · in 1 cylinder, roll or suppressor carriage which extends Φ * · V 25 over the web, and *: **: - made space blow a plurality in the transverse direction of the web successive air or • ··; 1; meadow beams from said one or more blowing hoods • · · towards the paper web to regulate the dry web content. 30 • φ * • · · 12. A method according to claim 11, characterized in that the dry content of the paper web is regulated by regulating ϊ. ·: The drying effect of the air or meadow beams according to the variations in dry content measured according to the paper web φ * ·, dryer cylinder group. • e · ··· • · 2 13. A method according to claim 11 or 12, characterized in that the dry content of the paper web is controlled by blowing air or meadow rays against the paper web from at least two successive blowing hoods extending over the web, and by separately controlling the drying effect of the air or which comes 5 from each blowing hood. 14. A method according to claim 11 or 12, characterized in that the dry content profile of the paper web is controlled in the transverse direction of the web by separately controlling the drying effect of the two or more successive air or meadow blades groups, or separately controlling each successive air jet of the web. drying effect. 15 Method according to any one of claims 11-14, characterized in that the dry content of the paper web is controlled by air jets blown against the paper web, whose drying effect of the air jets is controlled by controlling the temperature of the air jets, which temperature can vary between 40 ° C-500 ° C, advantageously 200 ° C-400 ° C. Method according to any of claims 11-14, characterized in that the dry content of the paper web is controlled ·· ♦ 1. · 25 by means of air jets blown against the paper web, whose drying effect of the air jet is controlled by to regulate the moisture content of the air streamers, which moisture content can vary between 0-300 g H20 / kg dry air. • 1 · 30 17. A method according to any of claims 11-14, characterized in. , that the dry content of the paper web is controlled by means of air jets blown against the paper web, whose: .i .: The drying effect of air jets is controlled by controlling the speed of the air jets, which speed is 40-200 m / s. Typically 50-150 m / s, most preferably 70-120 m / s. • φ · • · · · · 2 • · 3 18. A method according to claim 11, characterized in that replacement air supplied from the paper machine room is used in the air jet, circulating air from the hood of the drying section of the dryer or the device's own circulating air, whose air temperature is raised and / or whose air humidity level is lowered. towards the 5 paper web. 19. A method according to claim 11, characterized in that, in step (d), two or more inflation hoods or blower hoods are circulated for circulation air to the paper web, and the circulation air blown from each blower hood or blown hood is blown the various puffing hoods or their blocks by means of a common burner or other corresponding means that heats circulating air or that the circulating air blowing from each puffing hood or puffing hood block is heated by a burner which is separately integrated into each puffing hood or with another corresponding means that heats circulating air. The method according to claim 11, characterized in that the average dry content of the paper web is increased by * "*: embossing between 70% -95% , advantageously between 75% -85%. 21. A method according to claim 11, characterized in that air jets are blown against the web from two or more consecutive puffing hoods, wherein the drying effect of the air jets emanating from the first puffing hood is on average greater than the drying effect. of the air jets emanating from the following inflatable hoods. 35 I t · A drying section for paper web drying, comprising at least a drying cylinder group (R2), comprising drying cylinders (20, 24, 24 '; 410) and subsequently mounted blow drying modules (M0, Mi, M2, M3). 434, 634, 734) for drying a paper web (W), characterized in that the drying portion comprises - a measuring apparatus (34) for measuring the final moisture of the paper web (W) and means (36, 40) for controlling the blowing effect of at least one blowing unit (M0, Mi, M2, M3) and means for controlling the blowing speed, the temperature of the blowing medium and / or the humidity of the blowing medium. 10 Drying portion according to claim 22, characterized in that the drying portion therein comprises means (38) for controlling the meadow pressure of the drying cylinders (20, 24, 24 '). Drying portion according to claim 22 or 23, characterized in that the drying portion comprises controllers (36, 40, 400 / 40i, 402 and 403) for controlling the power of at least one blowing unit on the basis of the measurement results from the measuring apparatus (34). 20 Drying portion according to any of claims 22-24, characterized in that the measuring apparatus (34) for measuring the final moisture of the paper web (W) is located after the last drying cylinder group (Rio) of the drying section. A drying portion according to any one of claims 22-25, ***; characterized in that the drying portion comprises means (382, ··· · *). "383, 384, 385, 38β / 387, 38β / 389, 38io) to control the ·· · meadow pressure in one or more dryer cylinder groups (R2 - ..30) drying cylinder / dryer cylinders (20, 24, 24 '). The drying portion according to any of claims 22-26, characterized in that the drying portion comprises a memory itmti (42) which is coupled to regulate the drying effect #] ·. 35 to the control unit (36) to provide sort information about the · · · “in the paper type of the control system. • · t · » Drying portion according to any of claims 22-27, 51 119292, characterized in that the paper machine comprises devices for measuring any quality property of the paper web or its cross profile and means for measuring the blowing effect of at least one blowing unit 5 or its cross profile. 29. Apparatus for optimizing a paper web drying and / or power consumption in a paper machine dryer portion comprising 10 - at least one front dryer cylinder group (430), wherein the paper web is dried to a dry content of> 70%, advantageously> 75% and a device (428) adapted to said drying cylinder group (430) which regulates the paper web drying, characterized in that the device which controls the paper web drying comprises a blowing module, comprising - one or more blowing housings (28), ', 434, 434', 20 434 '') or equivalent extending over the web and one or more curved or linear counter surfaces, such as suction roll or vacuum carriage (26, 436, 436 ', 436' ') • · · * ·! · * Or equivalent, extending over the web, and ··: "which are adapted in the linear drying portion such that they form a gap-shaped space (438) through which" " the web (W, 418) can be guided, and: ***: - means (435) for blowing several air or meadow rays; *** · from said one or more blowing hoods or ··· corresponding to the paper web as it passes through the slit-shaped space. Device according to Claim 29, characterized in that the drying portion of the paper machine comprises a · at least one linear drying portion and one subsequently adapted, respectively. Device according to claim 29, characterized in that the blowing module is fitted immediately in front of the last drying cylinder group. Apparatus according to claim 29, characterized in that the blowing module is adapted immediately to the last drying cylinder group. Device according to Claim 29, characterized in that the blowing module comprises 2-3 in relation to the running direction of the paper web successive inflating hoods 10 (28, 28 ', 634, 634', 634 ") and 2-3 in relation to the running direction of the paper web successive suction rolls or suppressor slides (26, 636, 636 ', 636 "), which are adapted to each other to form between themselves a substantially horizontal spaced-apart space (638). 15 34. Apparatus according to claim 29, characterized in that the linear drying portion comprises a blow-out hood and 2-3 in relation to the running direction of the paper web, successive lower-pressure slides, which lower-pressure slides are adapted under the blow-out hood to form between the blown-out hood and lower-pressure cutter hood. A device according to claim 29, characterized in, n §; V 25 that the suction roll or suction roller of the inflating module * ί ** ϊ comprises means for creating a vacuum under the wire. A device according to claim 29, characterized in that the linear drying portion comprises an endless wire loop 30 (640) for supporting the paper web (618) in the slot-shaped • · · S · '.' the space (638) between one or more inflatable hoods (634, 634 ', 634 ") and one or more undercarriages (636, 636', 636"), wherein one or more undercarriages are adapted underneath The blower hood and the inside of the endless loop t · · ··· • * * • · • «*** 37. Apparatus according to claim 29, characterized in that an endless, in the linear drying section, has been arranged. The reversing rollers (442, 450) are guided, wire coil (440) to support the paper web in the slot-shaped space between one or more blow-off hoods and one or more suppressor slides. 38. Apparatus according to claim 29, characterized in that a closed transfer of paper web from the last front drying cylinder group to the linear drying part and a closed transfer of paper web from the linear drying part to the drying part to the drying part are arranged in the drying portion of the paper machine. 39. Apparatus according to claim 29, characterized in that the linear drying portion comprises - two or more blowing hoods or blowing hood blocks (634a, 634b, 634c), in which means (452, 454) have been arranged for blowing circulating air against the paper web. , and 20. common means (456) for heating circulating air in two or more blow-out hoods or blocks. and / or to reduce the moisture in it. Apparatus according to claim 29, characterized in, M · I *. 25 that the inflatable module comprises two or more inflatable hoods or inflatable hoods blocks, in which: e * has been provided means for blowing circulating air towards: ***; the paper web and in which separately, each has • • e integrated means for heating circulating air and / or removing the moisture from it. Apparatus according to claim 29, characterized in that each blowing cap comprises at least one, e ·· ί., Advantageously two or more rows of heel or slit. ·, 35 nozzles (535). , which rows run across the web, to • ♦ · blow air or meadow beams onto the paper web. 42. Apparatus according to claim 41, characterized in, that the slit or heel nozzles are formed in a flat hilc or slit disc (546) which is the bottom of the inflatable hood and is in the direction of the paper web, which is defined by the heel or slit disc. the gap-shaped space (538) and whose open area is 0.5-5% (1-2.5%), the distance between the heels being 10-100 mm (15-35 mm). 43. Apparatus according to claim 29, characterized in that the length of the linear drying portion is 1-20 m, preferably 5-10 m. 44. 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