JPH02502658A - How to dewater wet paper webs and introduce functional additives - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Methods for dewatering wet paper webs and introducing functional additives in industrial fields The present invention relates to a new method for manufacturing valves, paper and paperboard products, and In more detail, the post-forming process including the fluoridation stage, pressing stage and drying stage During the process, water is removed from the paper product, and the properties of the final product are changed and improved. It concerns a novel method.

Background technology Valve, paper, and paperboard manufacturing systems include a series of operations and processes. typical First, the wood is chemically treated or mechanically crushed to form the valve. Ke The medical valve needs to be cleaned. Both valves are often bleached. Ba Lube manufacturing, bleaching and cleaning are generally performed in a valve factory. followed by The operation is carried out in a paper mill.

Water is involved in various ways when producing paper from valve raw materials.

Water acts as a medium to transmit shear force to the fibers during beating, and also collects dispersed fibers. It functions as a dispersion medium to form a sheet with a desired composition.

Refining is one of the final operations, after which the process white It is diluted with water to form the headbox paper stock. Paper manufacturers need to understand this important Control operations to optimize subsequent process and physical property parameters can.

In refining, valve slurry is passed through a series of metal disks that rotate at high speed in a controlled manner. pumped through. During refining, cellulose fibers are expanded, cut, Dissociation promotes fibrillation. This fibrillation causes fibers to form during papermaking. Increased number of contact points between each other for better adhesion during subsequent pressing and drying operations do. For example, a sheet formed from unbeaten bulb waste has a low density and either It sounds soft and weak, but if you beat the same valve well, the paper you get will be very strong. It becomes much denser, harder, and stronger.

White water is added to the valve slurry before it is sent to the headbox after refining. added to reduce consistency.

The solids concentration in the headbox papermaking raw material is called “consistency” and is generally It is 0.2 to 1%. In general, the lower the consistency, the more improves uniformity. The papermaking raw material is sent under pressure from the head box to the papermaking section (wire). It will be done. Current papermaking machines can move at speeds of approximately 700 to 2000 m/min. Ru.

Continuous sheet forming and drying operations can be carried out using three different types of equipment: Paper machines, Fourdrinier paper machines (i.e. single wire paper machines) and twin wire paper machines It can be done by machine. In a circular wire paper machine, a cylinder covered with wire is It is installed in a vat containing the fiber slurry, and is controlled by the rotation of the cylinder. Water thus enters the inside through the screen and forms a paper web on the outside of the cylinder. It will be done. The wet web is removed at the top of the cylinder and passed between press rolls. The water is removed by steam heating and then passed through a cylindrical dryer tube heated by steam. long Mesh paper machines are more complex, but essentially run long, continuous synthetic fibers or wires. It consists of an ear screen (“wire”) that allows drainage It is supported in various ways to make it easier. via headbox and slice The fiber slurry introduced at one end of the lever machine is water is lost and a web is formed on the screen. This web is based on circular mesh paper making. As in the case of the machine, it is sent to the pressing and drying section.

The twin-wire paper machine is the latest development and basically consists of Consists of two wires. This twin wire paper machine is especially suitable for lightweight sheets, Fourdrinier paper machine in many paper making machines such as tissue, paper towel, newspaper etc. It has replaced the final process of The twin wire paper machine is capable of producing high-quality paper and cardboard. It has also been successfully operated in the manufacture of cores and liners. twin wire paper making The machine uses pressure, rather than suction, to expel water from the slurry. between slurry The two wires sandwiched between the cylinders or one layer of support rods or support foils are has been done. The support structure is inserted through the slurry by applying tension to the outer wire. Pressure is transmitted to the structure and the pressurized slurry is transferred to one or both wires. dehydrated through the

Typically, papermaking raw materials are processed through one or more screens, i.e., after conditioning and diluting the raw materials. It passes through a filtration device to remove impurities and is sent to the paper machine. Paper manufacturing raw material is flow spray Slurry enters the feeder, flows uniformly across the width of the paper machine, and exits from the flow spreader. enters the head box. In the headbox, agitation prevents fiber agglomeration. so that the slurry flows through the slice at the required velocity and lands on the moving wire. Pressure is applied to the sea urchin.

This wire is passed over the pre-stroll at the lead-in end and the couch roll at the discharge end. has been done. For the most part between these two rolls, the wire is connected to the table roll and , foil and supported by a suction box. Substantial vacuum force is downstream nip This vacuum force is generated between the table roll and the wire. Dewatering of the slurry is promoted. However, as the wire speed increases, the suction becomes stronger. If the wire becomes too tight, the wire will snake, resulting in the papermaking material being thrown into the air. . Use foil to control dehydration. The foil is shaped like a feather A member that supports the wire and creates a vacuum in the downstream nip. foil shape can be varied to achieve optimal conditions. Wire and sheet are foil Or pass through the suction box after passing through the table roll, and this suction box moisture is removed. Most machines have a suction cooler for better water removal. It also has Tyrol.

Most commonly, the paper web is It is formed. The papermaking raw material supplied from slices is a dispersion of fibers dispersed in water. 0.2 to 0%, typically in layers 6 to 18 mm deep and several meters wide or less. Contains dry solids. Raw materials for papermaking are synthetic fibers or metal woven fabrics. The water is then placed on an endless belt called a wire, and dehydrated. Non At low speeds, gravity is the largest contributor to dehydration. At higher speeds, gravity's The effect is negligible compared to dewatering components (i.e. table rolls or foils). Become so. When the wire moves and the papermaking raw material concentration reaches approximately 2%, the appearance changes occur. At this level, the surface appears to have stopped moving and the liquid light It loses its luster and becomes dull in appearance.

At this stage in the process, a dewatering member is used to remove water and form a web. is no longer effective. Then the consolidation is done by the action of the suction box. (solidification) begins. Applying pressure with a lightweight permeable roller slightly regenerates the fibers. It is still possible to arrange them. The unrolled web is pressed and dried and finished.

The consistency of the sheet emerging from the wet edge is 18-23%. follow to further mechanically remove water without adversely affecting the properties of the sheet. is possible. This is accomplished in a rotary press. How many rows A tally press is installed in the paper making machine. This press roll is solid or It is hollow and has holes. Suction is often done from inside the roll. sheet passes through the presses on a continuous felt (for each press the felt 1 piece). Felt has the role of a conveyor belt and a porous water absorber. There is.

Usually the water content in the sheet is reduced by pressing without crushing with crushing. can be reduced to a consistency of about 30-40%.

Squashing with crushing, i.e. creating a direct flow of water into the sheet, is a Occurs when pressing wet sheets with excessive pressure. With this crash Collapse can be avoided by gradually applying pressure. In other words, the pressure When added gradually, a small amount of water is removed first to avoid fiber separation. Also , change the structure of press rolls and felt to avoid crushing with crushing At the same time, the water removal rate can also be improved. The sheet is heated as water is removed. It becomes stronger and able to withstand more and more pressure.

The thicker the paper product, the greater the risk of collapse with crushing; It is especially important to gradually increase the pressure in the case of Play with multi-stage cylinder Soaked boards have high moisture content and are at risk of collapsing with delamination and crushing. .

Once the consistency is around 30-40%, no further water removal is possible by mechanical means. drying by evaporation is required. This is expensive This is a process that often becomes a bottleneck in papermaking. The dryer section , usually containing a series of steam-heated cylinders. Seat moves from cylinder to cylinder Both sides of the wet paper alternately contact the heated surface as it moves towards the surface. most places With the exception of heavy board, fabrics with carefully controlled vapor and air permeability are used. The sheet is held tightly against the surface of the dryer through the hook. Heat moistened from heating cylinder Transfer to a sheet and let the water evaporate. Water vapor is removed by an air system. Big Most dryer sections are covered with a hood that collects and processes air to keep it cool. Heat is recovered in the earth. The final consistency of the sheet after drying is! ! Construction The amount varies depending on the type of paper product, but is usually about 92-96% by weight.

The efficiency of the drying sequence is determined by the pressure applied when squeezing the wet web between the felts. size, the efficiency with which water condenses and is physically removed in the dryer cylinder, and the transport If felt is present, the type and characteristics of the felt and each dryer. It depends on factors such as the ventilation of the pockets in between. During this drying sequence, Product consistency ranges from about 30-40% of the introduction level to the dry paper product at the exit. This increases to a level of 92-96%.

The energy required to remove water depends on the form of water present in the paper product.

Most of the free eternity present in excess of the amount needed to saturate the wt fibers is It can be removed on the wire by force or suction. Water due to capillary action Excess free water is removed by a pressing operation. the most tightly held water (i.e. water in the lumens and pores of the fiber wall) requires considerably more energy to remove. Requires. This operation is generally accomplished by thermal drying.

In the early stages of drying, the fibers slide freely over each other, but as free water is removed, the fibers The fibers approach each other and bonding begins to occur. The main reason for the fibers to approach each other at this stage is This is caused by surface tension. The final bond between the fibers is achieved by intermolecular attraction.

Bonding between fibers does not occur significantly until the consistency exceeds about 40%. However, once the critical dry light point is reached, contraction begins and bonding begins to occur.

In summary, there are three steps required to form a final paper product from wood pulp: All involve the removal of water from fibers or webs: 1) Depositing the pulp onto a screen (or "wire") to create a web of paper fibers form. This stage is known as the initial stage of web formation, but the valve By feeding a low concentration aqueous dispersion solution (i.e. 0.2-1%) onto the screen. It will be realized. Create this screen and vacuum or suction power if necessary. The consistency of the web is increased to about 18-23%.

2) The “press section” compresses or squeezes the web to remove further water. Ru. This operation involves multiple felt presses or felt strips in contact with each web. This is realized by a series of rollers with a root. This press operation gives you extra freedom Some of the long-lived capillary water is removed, and the consistency of the web is approximately 30%. ~40% by weight.

3) "In the drying section j, the web is dried using a steam heating device. step, the amount of residual moisture in the web is reduced to the amount desired for the specific end product. However, the web consistency will typically be about 92-96% by weight.

As already explained, the greatest amount of energy is consumed in the drying process of paper products. for example , when manufacturing cardboard products such as boards, 8% of the water vapor used in paper mills is It has also been reported that 8.6% is used in drying cylinders. .

Drying operations are relatively expensive processes, and drying costs are always a factor in the final paper product process. Accounts for the majority of costs. Therefore, the savings in energy consumption during the drying stage is directly This leads to reduced manufacturing costs.

Summary of the invention The present invention provides a method for waving paper products during the consolidation stage, pressing stage, and drying stage. This invention relates to a method for increasing the removal rate of water from a web. Treatment with at least one water-insoluble solvent preferably wets the fibers and removes the water from the web. Replace at least part of it. This solvent can be used “straight” (i.e. alone or (almost pure) or in the form of an emulsion of solvent in water. can be used. Using a solvent-in-water emulsion If the emulsion is used during or immediately after the pressing operation. is preferred. This processing step includes a sufficient amount of water to completely wet the fibers in the web. It also includes adding a solvent to displace some of the water in the web. The fiber is pressed Can be wetted with the above solvents before production, during or after the press operation. .

Treat the web with one portion of solvent before the pressing operation and another portion of the solvent during the pressing operation. It can also be processed with Alternatively, the solvent can be introduced continuously during the press operation. Can also be done. Additionally, the solvent can be applied directly to the web or at the press section. It can also be applied to the belt and transferred indirectly to the web.

Preferred solvents include paraffinic, aliphatic or aromatic organic compounds and It is a logenated hydrocarbon. In the above method, at least one additive is added to the solvent. to modify or improve the properties of the final product before treating the web with solvents. included. By applying maximum amount of this solvent/additive mixture after pressing , it is preferable to optimally improve the properties.

The present invention feeds the valve onto the screen to form a web of paper fibers, and the felt Some of the water from the web deposited by pressing the web with a pressing means having a pressing surface Various paper product manufacturing processes that involve removing and drying the web after pressing It is also about improvement. One improvement is to reduce the pressing surface of the felt by a sufficient amount. In both cases, water on the felt surface is replaced by treatment with one kind of water-insoluble solvent. child The solvent wets the fibers of the web, increases consistency, and improves the press section. energizes the web and allows water to be more easily removed from the web during press operations. Ru. The solvent is supplied to the felt surface intermittently or continuously. of the above final paper products. Additives that modify or improve properties may be added prior to processing in the press section. can be added to the solvent later.

In another embodiment, the improved method includes adding at least one non-aqueous solvent to the pressing stage and/or the water-insoluble solvent. or used during the drying stage to displace at least some of the water in the web and press There is a point in increasing the drying rate of the coated web. This method allows you to press the web treated with a first portion of solvent during pressing, and further treated with a first portion of this solvent after the pressing operation. Further processing is performed by part 2. Also, if necessary, perform a final update before processing the web. Chemical additives may be added to one or both of the above solvents to improve the properties of the finished paper product. You can also add

Another embodiment provides at least one water-insoluble solvent in the web during the pressing step. Drying by displacing water and increasing the amount of press of the web being dried during the drying stage. Increase productivity of paper products. This improvement reduces the amount of energy consumed to dry the web. The amount of energy consumed decreases, and productivity improves with the same amount of energy consumed. production This means that the amount of energy consumed increases significantly or energy consumption decreases significantly. There is a great economic appeal in adopting the inventive method.

The invention also improves at least one property of the paper product after the formation of the paper web. It also relates to methods. In this method, at least one non-alcoholic acid is added before pressing the web. Treat the web with a sufficient amount of a water-soluble solvent to displace at least a portion of the water in the web and Improves at least one property of the final paper product by applying greater compression during compression. Improve. Adding to the solvent at least one additive that improves the properties of the paper product Both are possible.

Additionally, after the web is pressed, the solvent/additive or solvent emulsion/additive can also be treated to improve the properties of the final paper product. This example shows the maximum amount of additives. is also an effective application.

Such property-improving additives include solvent or solvent/emulsion additives prior to pressing operations. By using it together with the It is possible to improve the coloring properties and make it possible to change the color or whitening. can.

Even without additives, some properties of the final paper product can be improved by the addition of solvents, as mentioned above. will improve. That is, the thickness is reduced, the strength is increased, the uniformity is increased, and the The smoothness is increased and the printing properties are improved.

Another embodiment relates to an improvement in a pressing means for partially removing water from a web of paper products. do. Such pressing means usually have a felt surface in contact with the web. , the improvement of the present invention is that the felt surface of this pressing means is coated with a sufficient amount of non-aqueous solvent. treatment to displace at least a portion of the water between the felt surface and the web.

This increases the amount of water removed from the web during operation of the press means.

The present invention is a paper product manufacturing device for valve refining, process, and transfer. , and also relates to a papermaking system that uses water as a medium for the formation of a paper web.

Typically, paper product manufacturing equipment includes a web forming means and a valve above the web forming means. means for depositing and pressing means for removing a portion of the water from the web; drying means. The improvement of the present invention is that after the refining stage, in the consolidation stage, pressing stage, and drying stage by replacing with a water-insoluble solvent. The purpose of this invention is to increase the rate of water removal from the web. Also, do not use water-insoluble solvents. water from the web during the pressing and drying stages. It is also possible to increase the removal rate.

Brief description of the drawing Comparing the properties of paper produced according to the invention with those of paper produced by conventional methods The advantages of this are shown in the accompanying drawings.

FIG. 1 is a diagram of a typical fourdrinier single wire paper machine.

Figure 2 shows the consistency of paper sheets produced by the method of the present invention and the conventional method. It is a graph showing the relationship between (%) and drying time.

FIG. 3 is a diagram showing the thickness of paper sheets produced by the method of the present invention and the conventional method. Ru.

Detailed description of the invention The present invention generally involves adding a water-insoluble organic solvent to a paper web after its formation. , preferably one that wets the fibers and thereby displaces water. As a result, The water removal rate during the pressing and/or drying stages is significantly improved.

The economic impact of this increased water removal rate is a substantial reduction in energy consumption. (i.e. approximately 35-50% savings in the drying section) It is in. Additionally, the speed of most papermaking machines is controlled by the dryer, which greatly reduces productivity. improves.

Before the drying stage, the solvent can be added in neat or emulsion form. This improves the properties of the final product. Improved physical properties include: There is a decrease in thickness, an increase in smoothness, and an increase in strength. In addition, wet strength or dry strength Physical properties such as strength, sizing properties, whitening, and color can be determined by adding the above solvent to the web. , or by adding known papermaking chemical additives, including dyes, into the solvent before application. This can be improved by doing so. These solvents and additives are in order to maximize retention in the web and thus optimize the cost efficiency of the additive. Preferably it is added or applied after the pressing step. Using this method , nearly 100% of the additives can be retained in the web. This amount is This is a much higher amount than could be achieved by adding additives.

The present invention preferably does not contain any polar groups which are liquid at normal operating temperatures. Any organic solvent can be used.

Such organic solvents include hexane, decane, kerosene, gasoline, and benzene. There are paraffinic, aliphatic, and aromatic organic solvents such as toluene and toluene. this These solvents have much lower surface tension and interfacial tension, so they wet the fibers better. , displaces the coexisting water and thus facilitates water removal in the later pressing and drying stages. become.

Additionally, the preferred solvents described above desirably have all of the following properties: 1) Low water solubility.

2) Less odor.

3) Less toxicity to operators.

4) It is inexpensive.

5) Low vapor pressure.

6) Low boiling point.

7) Low surface tension.

8) High dissolving power, ie, KB value.

Solvents with any flash point can be used, but only to minimize the risk of ignition or explosion. In order to reduce the amount of water, it is desirable to use a solvent with a relatively high flash point and appropriate vapor pressure.

Observe special fire and explosion precautions when using low flash point solvents. It is necessary to

Currently, odorless kerosene has the best balance of the above properties and is a typical It is considered to be a preferred solvent that meets most criteria for papermaking processes. but, Similar results can be obtained with a wide range of other solvents if appropriate precautions are taken. It will be done.

Some such solvents include halogenated solvents that are liquid in the temperature range of -20 to 150°C. Contains the (mainly chlorinated) organic compounds ethylene dichloride and carbon tetrachloride.

To dissolve and migrate a given chemical additive towards the web, the solubility A solvent with a higher butanol number (KB number) may be required. Optimal water replacement The present invention also includes cases where two or more types of solvents are used in combination to achieve the desired performance. be caught.

The above solvents are used neat (i.e. in near-pure solvent form) after the formation of the web. Preferably, it is applied directly at any point in the process. Solvent is applied directly to the web or applied to the felt side of the press or applied to the web before the drying section. can be migrated to the web. The amount of solvent used is not critical to the invention . The lower limit for the amount of solvent used is to at least partially wet the fibers of the web and In turn, the amount is sufficient to increase the water removal rate in later stages. The solution used The maximum amount of solvent depends on solvent condensation, heat transfer, or recirculation systems, depending on the cost and high cost of the solvent. determined by economic or practical considerations related to the efficiency gains achieved at the level . Also, as mentioned above, a solvent emulsion made by suspending a solvent in water can be used as a web. It can also be applied using.

Solvents can be introduced at any point in the papermaking process after web formation and before paper drying. can be entered. When added in the right amount to the web on the wire or during the press, the ency increases and the press section becomes activated. This is about 10% or more corresponds to an increase in Furthermore, due to increased consistency, drying section The water removal rate is also improved. The combination of these two factors can cause dry sex. can save 30-40% of the steam used in Depending on the selection, this combination can also greatly increase production output. .

The invention includes the addition of solvent at more than one point to achieve the special results already mentioned. Also included. Removal of water by solvent if added after the press section ratio is increased, and a decrease in thickness can be avoided. Also, if necessary, it can be used for paper manufacturing. Additives can also be added to the solvent at more than one point.

Although these solvents are more expensive than water, used solvents can be collected and recycled. is possible. This spent solvent can be recovered by various means, such as carbon adsorption or This can be achieved using a condenser, etc. After the solvent has completely separated from the water in the system ,Reuse. Other recovery methods known to those skilled in the art may also be used to recover the solvent. Ru.

If the solvent is applied in the form of an emulsion before the drying section, the consistency increasing the thickness and activating the press section to avoid thickness reduction. moreover allows a greater proportion of water to be removed in the drying section. Become.

In general, to achieve results comparable to direct solvent application, emulsion more fluid volume is required.

One aspect of the invention provides at least one non-aqueous material for treating press felts. The point is that a soluble organic solvent is used. This process ensures that at this stage of the papermaking process The amount of water removed increases significantly. As a result, product drying time is reduced and Accordingly, the required energy is significantly reduced.

In normal press section operation, the consistency increases to about 30-40% do. The remaining amount represents the approximate amount of water retained in the fiber. highly refined The refined and beaten valve can hold more water and once dried Pulp that has been removed usually retains less water. Treating the felt side of the press The use of water-insoluble solvents increased the uniformity of paper products, improving their uniformity and strength. Thinner products can be obtained. Also, a smoother paper product is obtained and the result is a smoother paper product. As a result, printing characteristics are improved.

The solvent can be applied to the felt intermittently or continuously. to felt Application of the solvent can be accomplished in any of a number of ways, for example by washing the filtrate. Shower, spray, or spray the solvent on both sides of the felt in the same way you would use it to clean the felt. or spraying methods. The only requirement is that the solvent completely wets the felt. to ensure that all or as much water as possible is displaced from the felt. That is. The solvent can also be applied in the form of an emulsion.

In a preferred embodiment, the felt is continuously coated with solvent to ensure that the system does not experience interruptions. I'll do my best. The solvent used to wet the felt is controlled in the method of the invention. is not important. From a practical point of view, it is best to use the least amount of solvent possible. cost and quantity should be minimized. Minimum amount of melt needed to apply to felt The agent depends on the amount of paper product that comes into contact with it and can be determined by the skilled person in the usual way. can be done. For best results, the felt surface must be evenly wetted with solvent. need to be.

Also, some of the solvent must be able to migrate into the paper web to help displace free water. No.

Another aspect of the invention is a solvent applied to the web to improve the properties of the final paper product. The point is that various chemical additives are added to the

The addition of such additives is preferred for imparting various properties to paper products. Conventional In technology, these additives are generally applied to the paper at the end of the wet run of the papermaking machine. Ru. This method ensures that less than 100% of the additive is retained in the final paper product; In many cases, the additives are carried away through the wire into the white water discharged; It's quite low, so it's not efficient.

Such chemical additives are used for purposes such as: 1) increasing strength; , 2) increase wet strength; 3) For internal sizing, 4) For coloring, 5) Improvement of white skin When such additives are introduced into the above solvent, these additives are The amount of additive retained in the paper is much increased compared to the method of introducing it at the end as in Equation 1. Add. As already explained, in the present invention, the amount of additive retained in the web is often It will be close to 100%. The retention efficiency of the method introduced at the end of wet type 1 is mainly Depending on retention during the first pass, little or no additive is lost in the present invention. It won't happen. Therefore, the same property improvement can be achieved with a smaller amount of additives, and the same When using a small amount of additives, the paper products are The characteristics can be further improved.

Example The scope of the invention is further illustrated in connection with the following examples. Examples are merely examples of the present invention. They merely indicate preferred embodiments and are not intended to limit the scope of the invention in any way. do not have.

Example 1 (comparative example) Paper sheets were soaked in bleached kraft hardwood bulbs with a consistency of 0.31%. It was manufactured from a liquid using the following procedure.

1. Form a web.

2. Press the web with 100 bond.

3. Record the weight of the pressed sheet.

4. Dry the sheet at 105°C for 1 minute.

5. Cool the sheet in a desiccator.

6. Record the weight of the sheet.

7. Repeat steps 4.5.6 until the weight of the paper becomes constant.

The table below summarizes data for five sheets.

Table 1 Characteristics of sheets at different drying times Consistency % and moisture content The percentage was calculated using the following formula.

Moisture content iL (%) = 100 - Consistency (%) Strength in Z direction The temperature was found to average 4.4 psi.

Example 2 The procedure of Example 1 was repeated, but after step 2 the sheet was soaked in carbon tetrachloride for 1 minute. The difference is that it was soaked and then pressed at 100 pounds. Next, the remaining of Example 1 The operations (ie, operations 3 to 9) were performed.

The results are shown in the table below.

Table ■ Sheet characteristics at different drying times The results of Example 1 and Example 2 were compared A graph is shown in FIG.

The Z-direction strength of these sheets was found to be on average 4.4 psi. this is about 45% greater than the non-solvent treated sheet.

The amount of heat required to dry these sheets to a consistency of 94% decreased by 36%. Energy savings are achieved with a consistency of 38.2 after pressing. One of the reasons is that the percentage has increased from 47.8% to 47.8%. energy saved Most of the energy is absorbed by solvent-treated sheets, as seen from the inflection point of the curve in Figure 2. This is due to the fact that the drying rate is increasing.

In this special case, 15% of the energy saved is due to the post-press funcystin. 21% due to increased drying rate, and 21% due to increased inherent drying rate; This is a 36% energy saving.

Example 3 One experiment was conducted using the methods described in Examples 1 and 2. In this experiment compares the papermaking method using carbon tetrachloride and kerosene with the traditional papermaking method using only water. Comparison 1. Figure 3 shows that the thickness of the hard sheet manufactured by the conventional method is carbon tetrachloride. It shows that it is thicker than those made with base solvents or kerosene.

It is clear that the present invention described above is designed to achieve the above object. Although obvious, it will be appreciated that many variations and implementations will occur to those skilled in the art. I wonder. The appended claims also cover all modifications that fall within the spirit and scope of the invention. and embodiments.

-mouth Thickness (a)te) Ko Submission of translation of written amendment (Article 184-8 of the Patent Law) August 24, 1989

Claims (9)

[Claims] 1. After web formation and before the web is dried in the drying stage, the web is coated with at least A non-polar solvent is added to at least part of the water between the fibers of the web during the pressing stage. Consolidation consisting of applying sufficient amounts to replace the Increases the rate of water removal from the web of paper products during the printing, pressing or drying stages. How to make it bigger. 2. The above web is treated with an emulsion of water suspended in oil, a non-polar solvent. and further apply the above emulsion before the web passes through the pressing stage. The method according to claim 1, characterized in that: 3. The above solvent is continuously introduced in the pressing stage, and the above solvent is further added to the paraffin-based , aliphatic, and aromatic organic compounds. Or the method described in 2. 4. Adding at least one functional chemical additive to the solvent before processing the web. characterized in that it further comprises an operation that alters or improves the properties of the final paper product. 4. The method according to claim 1, 2, or 3. 5. The pulp is deposited on a screen to form a web of paper fibers and then The web is deposited by pressing the web in a pressing means having a flat surface. of paper products, including the step of removing some of the water from the web and dry-smoking the pressed web. During manufacturing, the felt surface for pressing is treated with at least one non-polar solvent. , this solvent removes at least the water between the fibers of the web during subsequent pressing steps. A method characterized in that the method is migrated to the web in an amount sufficient to partially replace it. 6. The above surface treatment operation involves continuously introducing a solvent onto the pressing felt. 6. The method of claim 5, comprising: 7. The above felt processing operation intermittently introduces the solvent onto the pressing felt. 6. A method according to claim 5, comprising the steps of: 8. Add at least one functional chemical additive to the above solvent before processing the web. characterized in that it further comprises an operation that alters or improves the properties of the final paper product. 8. The method according to claim 6 or 7. 9. Forming a web in a method of increasing the rate of water removal from a web of paper products After and before drying in the drying stage, the moisture between the fibers of the web is at least partially removed. is replaced with at least one non-polar solvent to increase the drying rate of the web and the amount of energy required to increase the production rate of a product or dry a web A method characterized by reducing.